Cytosine to guanine base editor

ABSTRACT

Some aspects of this disclosure provide compositions, strategies, systems, reagents, methods, and kits that are useful for the targeted editing of nucleic acids, including editing a single site within the genome of a cell or subject, e.g., within the human genome. In some embodiments, fusion proteins capable of inducing a cytosine (C) to guanine (G) change in a nucleic acid (e.g., genomic DNA) are provided. In some embodiments, fusion proteins of a nucleic acid programmable DNA binding protein (e.g., Cas9) and nucleic acid editing proteins or protein domains, e.g., deaminase domains, polymerase domains, and/or base excision enzymes are provided. In some embodiments, methods for targeted nucleic acid editing are provided. In some embodiments, reagents and kits for the generation of targeted nucleic acid editing proteins, e.g., fusion proteins of a nucleic acid programmable DNA binding protein (e.g., Cas9), and nucleic acid editing proteins or domains, are provided.

RELATED APPLICATIONS

This application is a national stage filing under 35 U.S.C. § 371 of international PCT application, PCT/US2018/021878, filed Mar. 9, 2018, which claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application, U.S. Ser. No. 62/470,175, filed Mar. 10, 2017, each of which is incorporated herein by reference.

REFERENCE TO A SEQUENCE LISTING SUBMITTED AS A TEXT FILE VIA EFS-WEB

This application contains a Sequence Listing which has been submitted in ASCII format via EFS-Web and is hereby incorporated by reference in its entirety. Said ASCII copy, created on Apr. 14, 2021, is named H082470253US01-SUBSEQ-EPG and is 673,227 bytes in size.

BACKGROUND OF INVENTION

Targeted editing of nucleic acid sequences, for example, the targeted cleavage or the targeted introduction of a specific modification into genomic DNA, is a highly promising approach for the study of gene function and also has the potential to provide new therapies for human genetic diseases. Since many genetic diseases in principle can be treated by affecting a specific nucleotide change at a specific location in the genome (for example, a C to G or a G to C change in a specific codon of a gene associated with a disease), the development of a programmable way to achieve such precise gene editing represents both a powerful new research tool, as well as a potential new approach to gene editing-based therapeutics.

BRIEF SUMMARY OF INVENTION

Provided herein are compositions, kits, and methods of modifying a polynucleotide (e.g., DNA), for example, generating a cytosine to guanine mutation in a polynucleotide. As described in greater detail herein, base editing (e.g., C to G editing) was accomplished by removing a nucleobase (e.g., cytosine (C)), thereby generating an abasic site within a nucleic acid sequence. The nucleobase opposite the abasic site (e.g., guanine), is then replaced with a different nucleobase (e.g., cytosine), for example by an endogenous translesion polymerase. Base editing fusion proteins described herein are capable of generating specific mutations (e.g., C to G mutations), within a nucleic acid (e.g., genomic DNA), which can be used, for example, to treat diseases involving nucleic acid mutations, e.g., C to G or G to C mutations.

One example of a C to G base editor includes a fusion protein containing a nucleic acid programmable DNA binding protein (e.g., a Cas9 domain), a uracil DNA glycosylase (UDG) domain, and a cytidine deaminase. Without wishing to be bound by any particular theory, such a base editing fusion protein is capable of binding to a specific nucleic acid sequence (e.g., via the Cas9 domain), deaminating a cytosine within the nucleic acid sequence to a uridine, which can then be excised from the nucleic acid molecule by UDG. The nucleobase opposite the abasic site can then be replaced with another base (e.g., cytosine), for example by an endogenous translesion polymerase. Typically, base repair machinery (e.g., in a cell) replaces a nucleobase opposite an abasic site with a cytosine, although other bases (e.g., adenine, guanine, or thymine) may replace a nucleobase opposite an abasic site. Furthermore, it was found that incorporating a translesion polymerase into the base editor can increase the cytosine incorporation opposite an abasic site. Accordingly, base editors were engineered to incorporate various translesion polymerases to improve base editing efficiency. Translesion polymerases that increase the preference for C integration opposite an abasic site can improve C to G nucleobase editing. It should be appreciated that other translesion polymerases that preferentially integrate non-C nucleobases (e.g., adenine, guanine, and thymine), may be used to generate alternative mutations (e.g., C to A mutations).

As another example, base editing fusion proteins may include a nucleic acid programmable DNA binding protein (e.g., a Cas9 domain), and a base excision enzyme that removes a nucleobase (e.g., a cytosine). Rather than deaminating a cytosine to uridine and excising the uridine using a UDG, as described above, a base editor may include a base excision enzyme that recognizes and removes a nucleobase such as a cytosine or a thymine without first deaminating it. Accordingly, base editors (e.g., C to G base editors) have been engineered by fusing a nucleic acid programmable DNA binding protein (e.g., a Cas9 domain) to a base excision enzyme that removes cytosine or thymine from a nucleic acid molecule. Furthermore, as with the base editor described above, translesion polymerases were incorporated into this base editor to increase the cytosine incorporation opposite an abasic site generated by the base excision enzyme of the base editor. Exemplary base editing proteins and schematic representations outlining base editing strategies can be seen, for example, in FIGS. 1-6, 33-36, 40, and 52 .

In some embodiments, the disclosure provides fusion proteins that are capable of base editing. Exemplary base editing fusion proteins include the following. In some embodiments, the fusion protein includes (i) a nucleic acid programmable DNA binding protein (napDNAbp), (ii) a cytidine deaminase domain, and (iii) a uracil binding protein (UBP). In some embodiments, the fusion protein further comprises (iv) a nucleic acid polymerase domain (NAP). As another example, a fusion protein may comprise (i) a nucleic acid programmable DNA binding protein (napDNAbp), (ii) a cytidine deaminase domain, and (iii) a nucleic acid polymerase (NAP) domain. As another example, a fusion protein may comprise (i) a nucleic acid programmable DNA binding protein (napDNAbp), and (ii) a base excision enzyme (BEE). In some embodiments, the fusion protein further includes (iii) a nucleic acid polymerase (NAP) domain. Base editors and methods of using base editors are described below in further detail.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a general schematic illustrating C to T and C to G base editing. Certain DNA polymerases (e.g., translesion polymerases) are known to replace bases opposite abasic sites with G. One strategy to achieve C to G base editing is to induce the creation of an abasic site, then recruit or tether such a polymerase to replace the G opposite the abasic site with a C.

FIG. 2 shows a general schematic illustrating base editing via abasic site generation and base-specific repair for C to G editing.

FIG. 3 shows a schematic illustrating scheme 1 from FIG. 1 , where an abasic site is formed, for C to G base editing. If the abasic is generated efficiently, this can increase the total flux through C to G editing pathway.

FIG. 4 shows a schematic illustrating approach 1 for C to G base editing where an increase in abasic site formation is used. If the abasic is generated efficiently, for example by using a UDG domain and a translesion polymerase, this can increase the total flux through C to G editing pathway.

FIG. 5 shows a schematic illustrating the effect of UdgX on base editing. UdgX, an orthologue of UDG identified to bind tightly to Uracil with minimal uracil excising activity, increases the amount of C to G editing. In 1.) UdgX* is a variant of UDG which was determined to lack uracil binding activity via an in vitro assay. In 2.) UdgX_On is a variant which was shown to increase uracil excision through an in vitro assay. In 3.) UDG direct fusion excises uracil.

FIG. 6 shows a schematic (on the left) illustrating an exemplary C to T base editor (e.g., BE3), which contains a uracil glycosylase inhibitor (UGI), a Cas9 domain (e.g., nCas9), and a cytidine deaminase. On the right is a schematic illustrating a C to G base editor, which contains a uracil DNA glycosylase (UDG) (or variants thereof), a Cas9 domain (e.g., nCas9), and a cytidine deaminase.

FIG. 7 shows total editing percentages at the HEK2 site in WT Hap1 cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 8 shows total editing percentages at the HEK2 site with additional C to G base editors (BE3; BE3_UdgX; BE3_REV7; and SMUG1, where BE3 and BE3_UdgX are repeated from FIG. 4 ) in WT Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 9 shows the editing specificity ratio at the HEK2 site with various C to G base editors (BE3; BE3_UdgX; BE3_UdgX*; BE3_REV7; BE2_UDG; BE3_UDG BE2_UdgX_On; BE3_UdgX_On; and SMUG1) in WT Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from G to A, C, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 10 shows total editing percentages at the RNF2 site in WT Hap1 cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 11 shows total editing percentages at the RNF2 site with additional C to G base editors (BE3; BE3_UdgX; BE3_REV7; and SMUG1, where BE3 and BE3_UdgX are repeated from FIG. 7 ) in WT Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 12 shows editing specificity ratio at the RNF2 site with various C to G base editors (BE3; BE3_UdgX; BE3_UdgX*; BE3_REV7; BE2_UDG; BE3_UDG BE2_UdgX_On; BE3_UdgX_On; and SMUG1) in WT Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from G to A, C, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 13 shows total editing percentages at the FANCF site in WT Hap1 cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

FIG. 14 shows total editing percentages at the FANCF site with additional C to G base editors (BE3; BE3_UdgX; BE3_REV7; and SMUG1, where BE3 and BE3_UdgX are repeated from FIG. 10 ) in WT Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

FIG. 15 shows the editing specificity ratio at the FANCF site with various C to G base editors (BE3; BE3_UdgX; BE3_UdgX*; BE3_REV7; BE2_UDG; BE3_UDG BE2_UdgX_On; BE3_UdgX_On; and SMUG1) in WT Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from C to A, G, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 16 shows total editing percentages at the HEK2 site in UDG^(−/−) Hap1 cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 17 shows total editing percentages at the HEK2 site with additional C to G base editors (BE3; BE3_UdgX; BE3_REV7; and SMUG1, where BE3 and BE3_UdgX are repeated from FIG. 13 ) in UDG^(−/−) Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 18 shows editing specificity ratio at the HEK2 site with various C to G base editors (BE3; BE3_UdgX; BE3_UdgX*; BE3_REV7; BE2_UDG; BE3_UDG BE2_UdgX_On; BE3_UdgX_On; and SMUG1) in UDG^(−/−) Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from G to A, C, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 19 shows total editing percentages at the RNF2 site in UDG^(−/−) Hap1 cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 20 shows total editing percentages at the RNF2 site with additional C to G base editors (BE3; BE3_UdgX; BE3_REV7; and SMUG1, where BE3 and BE3_UdgX are repeated from FIG. 16 ) in UDG^(−/−) Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 21 shows the editing specificity ratio at the RNF2 site with various C to G base editors (BE3; BE3_UdgX; BE3_UdgX*; BE3_REV7; BE2_UDG; BE3_UDG BE2_UdgX_On; BE3_UdgX_On; and SMUG1) in UDG^(−/−) Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from G to A, C, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 22 shows total editing percentages at the FANCF site in UDG^(−/−) Hap1 cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

FIG. 23 shows total editing percentages at the FANCF site with additional C to G base editors (BE3; BE3_UdgX; BE3_REV7; and SMUG1, where BE3 and BE3_UdgX are repeated from FIG. 19 ) in UDG^(−/−) Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

FIG. 24 shows the editing specificity ratio at the FANCF site with various C to G base editors (BE3; BE3_UdgX; BE3_UdgX*; BE3_REV7; BE2_UDG; BE3_UDG BE2_UdgX_On; BE3_UdgX_On; and SMUG1) in UDG^(−/−) Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from C to A, G, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 25 shows total editing percentages at the HEK2 site with various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) in REV1^(−/−) Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 26 shows editing specificity ratio at the HEK2 site with various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) in REV1^(−/−) Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from G to A, C, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 27 shows total editing percentages at the RNF2 site with various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) in REV1^(−/−) Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C), as sequencing was performed on the DNA strand opposite of the strand containing the edited C.

FIG. 28 shows editing specificity ratio at the RNF2 site with various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) in REV1^(−/−) Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from G to A, C, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 29 shows total editing percentages at the FANCF site with various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) in REV1^(−/−) Hap1 cells. The top panel shows the raw editing values. The bottom panel shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

FIG. 30 shows editing specificity ratio at the FANCF site with various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) in REV1^(−/−) Hap1 cells. The top pane shows the total percentage of edits and the ratio of edits that have been made from C to A, G, or T. The bottom panel is a graphical representation of the specificity ratio values.

FIG. 31 shows a graphical representation of the raw editing values for the percent of total editing at the HEK2, RNF2, and FANCF sites using the indicated C to G base editors.

FIG. 32 shows a graphical representation of the specificity ratio for the percent of total editing at the HEK2, RNF2, and FANCF sites.

FIG. 33 shows a schematic illustrating an approach to increase in the incorporation of C opposite an abasic site, for C to G base editing. If the preference for C integration opposite an abasic site is increased, for example by using a polymerase (e.g., a translesion polymerase), the total C to G base editing will also be increased.

FIG. 34 shows a schematic illustrating an approach to increase in the incorporation of C opposite an abasic site, for C to G base editing. If the preference for C integration opposite an abasic site is increased, for example by incorporating a translesion polymerase into the base editor, the total C to G base editing may also be increased.

FIG. 35 shows a schematic illustrating the different polymerases that can be used in the C to G base editing approach of FIGS. 33 and 34 .

FIG. 36 shows a schematic (on the left) illustrating an exemplary C to T base editor (e.g., BE3), which contains a uracil glycosylase inhibitor (UGI), a Cas9 domain (e.g., nCas9), and a cytidine deaminase. On the right is a schematic illustrating a C to G base editor, which contains a translesion polymerase, a Cas9 domain (e.g., nCas9), and a cytidine deaminase.

FIG. 37 shows base editing at the HEK2 site in WT cells using base editors tethered to REV1, Pol Kappa, Pol Eta, and Pol Iota. C to G editing is graphically shown by dotted bars (G) going to filled bars (C) in the graphical representation on the right panel. Pol Kappa tethering dramatically increases the efficiency of C to G editing. Raw editing values are shown on the left panel.

FIG. 38 shows base editing at the RNF2 site in WT cells using base editors tethered to REV1, Pol Kappa, Pol Eta, and Pol Iota. C to G editing is graphically shown by dotted bars (G) going to filled bars (C) in the graphical representation on the right panel. Pol Kappa tethering dramatically increases the efficiency of C to G editing. Raw editing values are shown on the left panel.

FIG. 39 shows base editing at the FANCF site in WT cells using base editors tethered to REV1, Pol Kappa, Pol Eta, and Pol Iota. C to G editing is graphically shown by filled bars (C) going to dotted bars (G) in the graphical representation on the right panel. Pol Kappa tethering dramatically increases the efficiency of C to G editing. Raw editing values are shown on the left panel.

FIG. 40 shows a schematic (on the left) illustrating an exemplary C to G base editor, which contains a uracil DNA glycosylase (UDG), a translesion polymerase, a Cas9 domain (e.g., nCas9), and a cytidine deaminase. On the right is a schematic illustrating a C to G base editor, which contains a translesion polymerase, a Cas9 domain (e.g., nCas9), and a base excision enzyme (e.g., a UDG variant capable of excising a C or T residue).

FIG. 41 shows C to G base editing using the base editor illustrated in the left panel of FIG. 40 (base editor containing a uracil DNA glycosylase (UDG), a translesion polymerase, a Cas9 domain, and a cytidine deaminase) at HEK2, RNF2, and FANCF sites using either Pol Kappa or Pol Iota tethered constructs. C to G editing is graphically shown by dotted bars (G) going to filled bars (C) for HEK2 and RNF2, and filled bars (C) going to dotted bars (G) for FANCF.

FIG. 42 shows base editing at the HEK2 site in WT cells using base editors tethered to either Pol Kappa, Pol Eta, Pol Iota, and REV1, which are shown in the right panel of FIG. 40 (base editor containing a translesion polymerase, a Cas9 domain, and base excision enzyme (UDG 147) which excises T). The amount C to G is graphically illustrated at specific residues in the HEK2 site. UDG 147 is a UDG variant that directly removes T.

FIG. 43 shows base editing at the RNF2 site in WT cells using base editors tethered to either Pol Kappa, Pol Eta, Pol Iota, and REV1, which are shown in the right panel of FIG. 40 (base editor containing a translesion polymerase, a Cas9 domain, and base excision enzyme (UDG 147) which excises T). The amount C to G is graphically illustrated at specific residues in the HEK2 site. UDG 147 is a UDG variant that directly removes T.

FIG. 44 shows base editing at the FANCF site in WT cells using base editors tethered to either Pol Kappa, Pol Eta, Pol Iota, and REV1, which are shown in the right panel of FIG. 40 (base editor containing a translesion polymerase, a Cas9 domain, and base excision enzyme (UDG 147) which excises T). The amount C to G is graphically illustrated at specific residues in the HEK2 site. UDG 147 is a UDG variant that directly removes T.

FIG. 45 shows base editing at the HEK2 site in WT cells using base editors tethered to either Pol Kappa, Pol Eta, Pol Iota, and REV1, which are shown in the right panel of FIG. 40 (base editor containing a translesion polymerase, a Cas9 domain, and base excision enzyme (UDG 204) which excises C). The amount C to G is graphically illustrated at specific residues in the HEK2 site. UDG 204 is a UDG variant that directly removes C.

FIG. 46 shows base editing at the RNF2 site in WT cells using base editors tethered to either Pol Kappa, Pol Eta, Pol Iota, and REV1, which are shown in the right panel of FIG. 40 (base editor containing a translesion polymerase, a Cas9 domain, and base excision enzyme (UDG 204) which excises C). The amount C to G is graphically illustrated at specific residues in the HEK2 site. UDG 204 is a UDG variant that directly removes C.

FIG. 47 shows base editing at the FANCF site in WT cells using base editors tethered to either Pol Kappa, Pol Eta, Pol Iota, and REV1, which are shown in the right panel of FIG. 40 (base editor containing a translesion polymerase, a Cas9 domain, and base excision enzyme (UDG 204) which excises C). The amount C to G is graphically illustrated at specific residues in the HEK2 site. UDG 204 is a UDG variant that directly removes C.

FIG. 48 shows a schematic illustrating a role of MSH2 in base repair, where MSH2 may facilitate the conversion of a uracil (U) to a cytosine (C) in DNA.

FIG. 49 shows base editing at the HEK2 site in MSH2−/− cells using six base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C).

FIG. 50 shows base editing at the RNF2 site in MSH2−/− cells using six base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; and BE3_UDG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by dotted bars (G) going to filled bars (C).

FIG. 51 shows base editing at the FANCF site in MSH2−/− cells using six base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; and BE3 UNG). Raw editing values are shown in the left panel. The panel on the right shows a graphical representation of the raw editing values, where C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

FIG. 52 shows a schematic illustrating a base editing approach where a C to G base editor containing a UDG (or a UDG variant), a Cas9 (e.g., nCas9) domain, and a cytidine deaminase is expressed in trans with a translesion polymerase.

FIG. 53 shows base editing at the HEK2 site in HEK293 cells using five base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; and BE3_UDG) expressed, in trans, with various polymerases (Pol Kappa, Pol Eta, Pol Iota, REV1, Pol Beta, and Pol Delta). C to G base editing is graphically shown by dotted bars (G) going to filled bars (C).

FIG. 54 shows base editing at the RNF2 site in HEK293 cells using five base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; and BE3_UDG) expressed, in trans, with various polymerases (Pol Kappa, Pol Eta, Pol Iota, REV1, Pol Beta, and Pol Delta). C to G base editing is graphically shown by dotted bars (G) going to filled bars (C).

FIG. 55 shows base editing at the FANCF site in HEK293 cells using five base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; and BE3_UDG) expressed, in trans, with various polymerases (Pol Kappa, Pol Eta, Pol Iota, REV1, Pol Beta, and Pol Delta). C to G base editing is graphically shown by filled bars (C) going to dotted bars (G).

DEFINITIONS

As used herein and in the claims, the singular forms “a,” “an,” and “the” include the singular and the plural unless the context clearly indicates otherwise. Thus, for example, a reference to “an agent” includes a single agent and a plurality of such agents.

The term “deaminase” or “deaminase domain,” as used herein, refers to a protein or enzyme that catalyzes a deamination reaction. In some embodiments, the deaminase or deaminase domain is a cytidine deaminase, catalyzing the hydrolytic deamination of cytidine or deoxycytidine to uridine or deoxyuridine, respectively. In some embodiments, the deaminase or deaminase domain is a cytidine deaminase domain, catalyzing the hydrolytic deamination of cytosine to uracil. In some embodiments, the deaminase or deaminase domain is a naturally-occurring deaminase from an organism, such as a human, chimpanzee, gorilla, monkey, cow, dog, rat, or mouse. In some embodiments, the deaminase or deaminase domain is a variant of a naturally-occurring deaminase from an organism that does not occur in nature. For example, in some embodiments, the deaminase or deaminase domain is at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75% at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to a naturally-occurring deaminase from an organism.

The term “base editor (BE),” or “nucleobase editor (NBE)” refers to an agent comprising a polypeptide that is capable of making a modification to a base (e.g., A, T, C, G, or U) within a nucleic acid sequence (e.g., DNA or RNA). In some embodiments, the base editor is capable of deaminating a base within a nucleic acid. In some embodiments, the base editor is capable of deaminating a base within a DNA molecule. In some embodiments, the base editor is capable of deaminating a cytosine (C) in DNA. In some embodiments, the base editor is capable of excising a base within a DNA molecule. In some embodiments, the base editor is capable of excising an adenine, guanine, cytosine, thymine or uracil within a nucleic acid (e.g., DNA or RNA) molecule. In some embodiments, the base editor is a protein (e.g., a fusion protein) comprising a nucleic acid programmable DNA binding protein (napDNAbp) fused to a cytidine deaminase. In some embodiments, the base editor is fused to a uracil binding protein (UBP), such as a uracil DNA glycosylase (UDG). In some embodiments, the base editor is fused to a nucleic acid polymerase (NAP) domain. In some embodiments, the NAP domain is a translesion DNA polymerase. In some embodiments, the base editor comprises a napDNAbp, a cytidine deaminase and a UBP (e.g., UDG). In some embodiments, the base editor comprises a napDNAbp, a cytidine deaminase and a nucleic acid polymerase (e.g., a translesion DNA polymerase). In some embodiments, the base editor comprises a napDNAbp, a cytidine deaminase, a UBP (e.g., UDG), and a nucleic acid polymerase (e.g., a translesion DNA polymerase).

In some embodiments, the napDNAbp of the base editor is a Cas9 domain. In some embodiments, the base editor comprises a Cas9 protein fused to a cytidine deaminase. In some embodiments, the base editor comprises a Cas9 nickase (nCas9) fused to a cytidine deaminase. In some embodiments, the Cas9 nickase comprises a D10A mutation and comprises a histidine at residue 840 of SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any one of SEQ ID NOs: 4-26, which renders Cas9 capable of cleaving only one strand of a nucleic acid duplex. In some embodiments, the base editor comprises a nuclease-inactive Cas9 (dCas9) fused to a cytidine deaminase. In some embodiments, the dCas9 domain comprises a D10A and a H840A mutation of SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any one of SEQ ID NOs: 4-26, which inactivates the nuclease activity of the Cas9 protein.

The term “linker,” as used herein, refers to a bond (e.g., covalent bond), chemical group, or a molecule linking two molecules or moieties, e.g., two domains of a fusion protein, such as, for example, a nuclease-inactive Cas9 domain and a nucleic acid-editing domain (e.g., an cytidine deaminase). In some embodiments, a linker joins a gRNA binding domain of an RNA-programmable nuclease, including a Cas9 nuclease domain, and the catalytic domain of a nucleic-acid editing protein. In some embodiments, a linker joins a dCas9 and a nucleic-acid editing protein. Typically, the linker is positioned between, or flanked by, two groups, molecules, or other moieties and connected to each one via a covalent bond, thus connecting the two. In some embodiments, the linker is an amino acid or a plurality of amino acids (e.g., a peptide or protein). In some embodiments, the linker is an organic molecule, group, polymer, or chemical moiety. In some embodiments, the linker is 5-100 amino acids in length, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 30-35, 35-40, 40-45, 45-50, 50-60, 60-70, 70-80, 80-90, 90-100, 100-150, or 150-200 amino acids in length. Longer or shorter linkers are also contemplated. In some embodiments, a linker comprises the amino acid sequence SGSETPGTSESATPES (SEQ ID NO: 102), which may also be referred to as the XTEN linker. In some embodiments, a linker comprises the amino acid sequence SGGS (SEQ ID NO: 103). In some embodiments, a linker comprises (SGGS)_(n) (SEQ ID NO: 103), (GGGS)_(n) (SEQ ID NO: 104), (GGGGS)_(n) (SEQ ID NO: 105), (G)_(n) (SEQ ID NO: 121), (EAAAK)_(n) (SEQ ID NO: 106), (GGS)_(n)(SEQ ID NO: 122), SGSETPGTSESATPES (SEQ ID NO: 102), (XP)_(n) motif (SEQ ID NO: 123), SGGSSGSETPGTSESATPESSGGS (SEQ ID NO: 107), SGGSSGGSSGSETPGTSESATPESSGGSSGGS (SEQ ID NO: 108), GGSGGSPGSPAGSPTSTEEGTSESATPESGPGTSTEPSEGSAPGSPAGSPTSTEEGTSTE PSEGSAPGTSTEPSEGSAPGTSESATPESGPGSEPATSGGSGGS (SEQ ID NO: 109), SGGSGGSGGS (SEQ ID NO: 120), or a combination of any of these, wherein n is independently an integer between 1 and 30, and wherein X is any amino acid. In some embodiments, n is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15.

The term “mutation,” as used herein, refers to a substitution of a residue within a sequence, e.g., a nucleic acid or amino acid sequence, with another residue, or a deletion or insertion of one or more residues within a sequence. Mutations are typically described herein by identifying the original residue followed by the position of the residue within the sequence and by the identity of the newly substituted residue. Various methods for making the amino acid substitutions (mutations) provided herein are well known in the art, and are provided by, for example, Green and Sambrook, Molecular Cloning: A Laboratory Manual (4^(th) ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (2012)).

The term “uracil binding protein” or “UBP,” as used herein, refers to a protein that is capable of binding to uracil. In some embodiments, the uracil binding protein is a uracil modifying enzyme. In some embodiments, the uracil binding protein is a uracil base excision enzyme. In some embodiments, the uracil binding protein is a uracil DNA glycosylase (UDG). In some embodiments, a uracil binding protein binds uracil with an affinity that is at least 1%, 2%, 3%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or at least 95% of the affinity that a wild type UDG (e.g., a human UDG) binds to uracil.

The term “base excision enzyme” or “BEE,” as used herein, refers to a protein that is capable of removing a base (e.g., A, T, C, G, or U) from a nucleic acid molecule (e.g., DNA or RNA). In some embodiments, a BEE is capable of removing a cytosine from DNA. In some embodiments, a BEE is capable of removing a thymine from DNA. Exemplary BEEs include, without limitation UDG Tyr147Ala, and UDG Asn204Asp as described in Sang et al., “A Unique Uracil-DNA binding protein of the uracil DNA glycosylase superfamily,” Nucleic Acids Research, Vol. 43, No. 17 2015; the entire contents of which are hereby incorporated by reference.

The term “nucleic acid polymerase” or “NAP,” refers to an enzyme that synthesizes nucleic acid molecules (e.g., DNA and RNA) from nucleotides (e.g., deoxyribonucleotides and ribonucleotides). In some embodiments, the NAP is a DNA polymerase. In some embodiments, the NAP is a translesion polymerase. Translesion polymerases play a role in mutagenesis, for example, by restarting replication forks or filling in gaps that remain in the genome due to the presence of DNA lesions. Exemplary translesion polymerases include, without limitation, Pol Beta, Pol Lambda, Pol Eta, Pol Mu, Pol Iota, Pol Kappa, Pol Alpha, Pol Delta, Pol Gamma, and Pol Nu.

The term “nuclear localization sequence” or “NLS” refers to an amino acid sequence that promotes import of a protein into the cell nucleus, for example, by nuclear transport. Nuclear localization sequences are known in the art and would be apparent to the skilled artisan. In some embodiments, the NLS is a monopartite NLS. In some embodiments, the NLS is a bipartite NLS. Bipartite NLSs are separated by a relatively short spacer sequence (e.g., from 2-20 amino acids, from 5-15 amino acids, or from 8-12 amino acids). For example, NLS sequences are described in Plank et al., international PCT application, PCT/EP2000/011690, filed Nov. 23, 2000, published as WO/2001/038547 on May 31, 2001; and Kethar, K. M. V., et al., “Application of bioinformatics-coupled experimental analysis reveals a new transport-competent nuclear localization signal in the nucleoptotein of Influenza A virus strain” BMC Cell Biol, 2008, 9: 22; the contents of each of which are incorporated herein by reference for their disclosure of exemplary nuclear localization sequences. In some embodiments, a NLS comprises the amino acid sequence PKKKRKV (SEQ ID NO: 41), MDSLLMNRRKFLYQFKNVRWAKGRRETYLC (SEQ ID NO: 42), KRTADGSEFESPKKKRKV (SEQ ID NO: 43), KRGINDRNFWRGENGRKTR (SEQ ID NO: 44), KKTGGPIYRRVDGKWRR (SEQ ID NO: 45), RRELILYDKEEIRRIWR (SEQ ID NO: 46), or AVSRKRKA (SEQ ID NO: 47).

The term “nucleic acid programmable DNA binding protein” or “napDNAbp” refers to a protein that associates with a nucleic acid (e.g., DNA or RNA), such as a guide nuclic acid, that guides the napDNAbp to a specific nucleic acid sequence. For example, a Cas9 protein can associate with a guide RNA that guides the Cas9 protein to a specific DNA sequence that has complementary to the guide RNA. In some embodiments, the napDNAbp is a class 2 microbial CRISPR-Cas effector. In some embodiments, the napDNAbp is a Cas9 domain, for example a nuclease active Cas9, a Cas9 nickase (nCas9), or a nuclease inactive Cas9 (dCas9). Examples of nucleic acid programmable DNA binding proteins include, without limitation, Cas9 (e.g., dCas9 and nCas9), CasX, CasY, Cpf1, C2c1, C2c2, C2C3, and Argonaute. It should be appreciated, however, that nucleic acid programmable DNAbinding proteins also include nucleic acid programmable proteins that bind RNA. For example, the napDNAbp may be associated with a nucleic acid that guides the napDNAbp to an RNA. Other nucleic acid programmable DNA binding proteins are also within the scope of this disclosure, though they may not be specifically listed in this disclosure.

The term “Cas9” or “Cas9 domain” refers to an RNA-guided nuclease comprising a Cas9 protein, or a fragment thereof (e.g., a protein comprising an active, inactive, or partially active DNA cleavage domain of Cas9, and/or the gRNA binding domain of Cas9). A Cas9 nuclease is also referred to sometimes as a casn1 nuclease or a CRISPR (clustered regularly interspaced short palindromic repeat)-associated nuclease. CRISPR is an adaptive immune system that provides protection against mobile genetic elements (viruses, transposable elements and conjugative plasmids). CRISPR clusters contain spacers, sequences complementary to antecedent mobile elements, and target invading nucleic acids. CRISPR clusters are transcribed and processed into CRISPR RNA (crRNA). In type II CRISPR systems correct processing of pre-crRNA requires a trans-encoded small RNA (tracrRNA), endogenous ribonuclease 3 (mc) and a Cas9 protein. The tracrRNA serves as a guide for ribonuclease 3-aided processing of pre-crRNA. Subsequently, Cas9/crRNA/tracrRNA endonucleolytically cleaves linear or circular dsDNA target complementary to the spacer. The target strand not complementary to crRNA is first cut endonucleolytically, then trimmed 3′-5′ exonucleolytically. In nature, DNA-binding and cleavage typically requires protein and both RNAs. However, single guide RNAs (“sgRNA”, or simply “gNRA”) can be engineered so as to incorporate aspects of both the crRNA and tracrRNA into a single RNA species. See, e.g., Jinek M., Chylinski K., Fonfara I., Hauer M., Doudna J. A., Charpentier E. Science 337:816-821(2012), the entire contents of which is hereby incorporated by reference. Cas9 recognizes a short motif in the CRISPR repeat sequences (the PAM or protospacer adjacent motif) to help distinguish self versus non-self. Cas9 nuclease sequences and structures are well known to those of skill in the art (see, e.g., “Complete genome sequence of an M1 strain of Streptococcus pyogenes.” Ferretti et al., J. J., McShan W. M., Ajdic D. J., Savic D. J., Savic G., Lyon K., Primeaux C., Sezate S., Suvorov A. N., Kenton S., Lai H. S., Lin S. P., Qian Y., Jia H. G., Najar F. Z., Ren Q., Zhu H., Song L., White J., Yuan X., Clifton S. W., Roe B. A., McLaughlin R. E., Proc. Natl. Acad. Sci. U.S.A. 98:4658-4663(2001); “CRISPR RNA maturation by trans-encoded small RNA and host factor RNase III.” Deltcheva E., Chylinski K., Sharma C. M., Gonzales K., Chao Y., Pirzada Z. A., Eckert M. R., Vogel J., Charpentier E., Nature 471:602-607(2011); and “A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity.” Jinek M., Chylinski K., Fonfara I., Hauer M., Doudna J. A., Charpentier E. Science 337:816-821(2012), the entire contents of each of which are incorporated herein by reference). Cas9 orthologs have been described in various species, including, but not limited to, S. pyogenes and S. thermophilus. Additional suitable Cas9 nucleases and sequences will be apparent to those of skill in the art based on this disclosure, and such Cas9 nucleases and sequences include Cas9 sequences from the organisms and loci disclosed in Chylinski, Rhun, and Charpentier, “The tracrRNA and Cas9 families of type II CRISPR-Cas immunity systems” (2013) RNA Biology 10:5, 726-737; the entire contents of which are incorporated herein by reference. In some embodiments, a Cas9 nuclease has an inactive (e.g., an inactivated) DNA cleavage domain, that is, the Cas9 is a nickase.

A nuclease-inactivated Cas9 protein may interchangeably be referred to as a “dCas9” protein (for nuclease-“dead” Cas9). Methods for generating a Cas9 protein (or a fragment thereof) having an inactive DNA cleavage domain are known (See, e.g., Jinek et al., Science. 337:816-821(2012); Qi et al., “Repurposing CRISPR as an RNA-Guided Platform for Sequence-Specific Control of Gene Expression” (2013) Cell. 28; 152(5):1173-83, the entire contents of each of which are incorporated herein by reference). For example, the DNA cleavage domain of Cas9 is known to include two subdomains, the HNH nuclease subdomain and the RuvC1 subdomain. The HNH subdomain cleaves the strand complementary to the gRNA, whereas the RuvC1 subdomain cleaves the non-complementary strand. Mutations within these subdomains can silence the nuclease activity of Cas9. For example, the mutations D10A and H840A completely inactivate the nuclease activity of S. pyogenes Cas9 (Jinek et al., Science. 337:816-821(2012); Qi et al., Cell. 28; 152(5):1173-83 (2013)). In some embodiments, proteins comprising fragments of Cas9 are provided. For example, in some embodiments, a protein comprises one of two Cas9 domains: (1) the gRNA binding domain of Cas9; or (2) the DNA cleavage domain of Cas9. In some embodiments, proteins comprising Cas9 or fragments thereof are referred to as “Cas9 variants.” A Cas9 variant shares homology to Cas9, or a fragment thereof. For example a Cas9 variant is at least about 70% identical, at least about 80% identical, at least about 90% identical, at least about 95% identical, at least about 96% identical, at least about 97% identical, at least about 98% identical, at least about 99% identical, at least about 99.5% identical, or at least about 99.9% identical to wild type Cas9. In some embodiments, the Cas9 variant may have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to wild type Cas9. In some embodiments, the Cas9 variant comprises a fragment of Cas9 (e.g., a gRNA binding domain or a DNA-cleavage domain), such that the fragment is at least about 70% identical, at least about 80% identical, at least about 90% identical, at least about 95% identical, at least about 96% identical, at least about 97% identical, at least about 98% identical, at least about 99% identical, at least about 99.5% identical, or at least about 99.9% identical to the corresponding fragment of wild type Cas9. In some embodiments, the fragment is at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95% identical, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% of the amino acid length of a corresponding wild type Cas9.

In some embodiments, the fragment is at least 100 amino acids in length. In some embodiments, the fragment is at least 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, or 1300 amino acids in length. In some embodiments, wild type Cas9 corresponds to Cas9 from Streptococcus pyogenes (NCBI Reference Sequence: NC_017053.1, SEQ ID NO: 1 (nucleotide); SEQ ID NO: 4 (amino acid)).

(SEQ ID NO: 1) ATGGATAAGAAATACTCAATAGGCTTAGATATCGGCACAAATAGCGTCGG ATGGGCGGTGATCACTGATGATTATAAGGTTCCGTCTAAAAAGTTCAAGG TTCTGGGAAATACAGACCGCCACAGTATCAAAAAAAATCTTATAGGGGCT CTTTTATTTGGCAGTGGAGAGACAGCGGAAGCGACTCGTCTCAAACGGAC AGCTCGTAGAAGGTATACACGTCGGAAGAATCGTATTTGTTATCTACAGG AGATTTTTTCAAATGAGATGGCGAAAGTAGATGATAGTTTCTTTCATCGA CTTGAAGAGTCTTTTTTGGTGGAAGAAGACAAGAAGCATGAACGTCATCC TATTTTTGGAAATATAGTAGATGAAGTTGCTTATCATGAGAAATATCCAA CTATCTATCATCTGCGAAAAAAATTGGCAGATTCTACTGATAAAGCGGAT TTGCGCTTAATCTATTTGGCCTTAGCGCATATGATTAAGTTTCGTGGTCA TTTTTTGATTGAGGGAGATTTAAATCCTGATAATAGTGATGTGGACAAAC TATTTATCCAGTTGGTACAAATCTACAATCAATTATTTGAAGAAAACCCT ATTAACGCAAGTAGAGTAGATGCTAAAGCGATTCTTTCTGCACGATTGAG TAAATCAAGACGATTAGAAAATCTCATTGCTCAGCTCCCCGGTGAGAAGA GAAATGGCTTGTTTGGGAATCTCATTGCTTTGTCATTGGGATTGACCCCT AATTTTAAATCAAATTTTGATTTGGCAGAAGATGCTAAATTACAGCTTTC AAAAGATACTTACGATGATGATTTAGATAATTTATTGGCGCAAATTGGAG ATCAATATGCTGATTTGTTTTTGGCAGCTAAGAATTTATCAGATGCTATT TTACTTTCAGATATCCTAAGAGTAAATAGTGAAATAACTAAGGCTCCCCT ATCAGCTTCAATGATTAAGCGCTACGATGAACATCATCAAGACTTGACTC TTTTAAAAGCTTTAGTTCGACAACAACTTCCAGAAAAGTATAAAGAAATC TTTTTTGATCAATCAAAAAACGGATATGCAGGTTATATTGATGGGGGAGC TAGCCAAGAAGAATTTTATAAATTTATCAAACCAATTTTAGAAAAAATGG ATGGTACTGAGGAATTATTGGTGAAACTAAATCGTGAAGATTTGCTGCGC AAGCAACGGACCTTTGACAACGGCTCTATTCCCCATCAAATTCACTTGGG TGAGCTGCATGCTATTTTGAGAAGACAAGAAGACTTTTATCCATTTTTAA AAGACAATCGTGAGAAGATTGAAAAAATCTTGACTTTTCGAATTCCTTAT TATGTTGGTCCATTGGCGCGTGGCAATAGTCGTTTTGCATGGATGACTCG GAAGTCTGAAGAAACAATTACCCCATGGAATTTTGAAGAAGTTGTCGATA AAGGTGCTTCAGCTCAATCATTTATTGAACGCATGACAAACTTTGATAAA AATCTTCCAAATGAAAAAGTACTACCAAAACATAGTTTGCTTTATGAGTA TTTTACGGTTTATAACGAATTGACAAAGGTCAAATATGTTACTGAGGGAA TGCGAAAACCAGCATTTCTTTCAGGTGAACAGAAGAAAGCCATTGTTGAT TTACTCTTCAAAACAAATCGAAAAGTAACCGTTAAGCAATTAAAAGAAGA TTATTTCAAAAAAATAGAATGTTTTGATAGTGTTGAAATTTCAGGAGTTG AAGATAGATTTAATGCTTCATTAGGCGCCTACCATGATTTGCTAAAAATT ATTAAAGATAAAGATTTTTTGGATAATGAAGAAAATGAAGATATCTTAGA GGATATTGTTTTAACATTGACCTTATTTGAAGATAGGGGGATGATTGAGG AAAGACTTAAAACATATGCTCACCTCTTTGATGATAAGGTGATGAAACAG CTTAAACGTCGCCGTTATACTGGTTGGGGACGTTTGTCTCGAAAATTGAT TAATGGTATTAGGGATAAGCAATCTGGCAAAACAATATTAGATTTTTTGA AATCAGATGGTTTTGCCAATCGCAATTTTATGCAGCTGATCCATGATGAT AGTTTGACATTTAAAGAAGATATTCAAAAAGCACAGGTGTCTGGACAAGG CCATAGTTTACATGAACAGATTGCTAACTTAGCTGGCAGTCCTGCTATTA AAAAAGGTATTTTACAGACTGTAAAAATTGTTGATGAACTGGTCAAAGTA ATGGGGCATAAGCCAGAAAATATCGTTATTGAAATGGCACGTGAAAATCA GACAACTCAAAAGGGCCAGAAAAATTCGCGAGAGCGTATGAAACGAATCG AAGAAGGTATCAAAGAATTAGGAAGTCAGATTCTTAAAGAGCATCCTGTT GAAAATACTCAATTGCAAAATGAAAAGCTCTATCTCTATTATCTACAAAA TGGAAGAGACATGTATGTGGACCAAGAATTAGATATTAATCGTTTAAGTG ATTATGATGTCGATCACATTGTTCCACAAAGTTTCATTAAAGACGATTCA ATAGACAATAAGGTACTAACGCGTTCTGATAAAAATCGTGGTAAATCGGA TAACGTTCCAAGTGAAGAAGTAGTCAAAAAGATGAAAAACTATTGGAGAC AACTTCTAAACGCCAAGTTAATCACTCAACGTAAGTTTGATAATTTAACG AAAGCTGAACGTGGAGGTTTGAGTGAACTTGATAAAGCTGGTTTTATCAA ACGCCAATTGGTTGAAACTCGCCAAATCACTAAGCATGTGGCACAAATTT TGGATAGTCGCATGAATACTAAATACGATGAAAATGATAAACTTATTCGA GAGGTTAAAGTGATTACCTTAAAATCTAAATTAGTTTCTGACTTCCGAAA AGATTTCCAATTCTATAAAGTACGTGAGATTAACAATTACCATCATGCCC ATGATGCGTATCTAAATGCCGTCGTTGGAACTGCTTTGATTAAGAAATAT CCAAAACTTGAATCGGAGTTTGTCTATGGTGATTATAAAGTTTATGATGT TCGTAAAATGATTGCTAAGTCTGAGCAAGAAATAGGCAAAGCAACCGCAA AATATTTCTTTTACTCTAATATCATGAACTTCTTCAAAACAGAAATTACA CTTGCAAATGGAGAGATTCGCAAACGCCCTCTAATCGAAACTAATGGGGA AACTGGAGAAATTGTCTGGGATAAAGGGCGAGATTTTGCCACAGTGCGCA AAGTATTGTCCATGCCCCAAGTCAATATTGTCAAGAAAACAGAAGTACAG ACAGGCGGATTCTCCAAGGAGTCAATTTTACCAAAAAGAAATTCGGACAA GCTTATTGCTCGTAAAAAAGACTGGGATCCAAAAAAATATGGTGGTTTTG ATAGTCCAACGGTAGCTTATTCAGTCCTAGTGGTTGCTAAGGTGGAAAAA GGGAAATCGAAGAAGTTAAAATCCGTTAAAGAGTTACTAGGGATCACAAT TATGGAAAGAAGTTCCTTTGAAAAAAATCCGATTGACTTTTTAGAAGCTA AAGGATATAAGGAAGTTAAAAAAGACTTAATCATTAAACTACCTAAATAT AGTCTTTTTGAGTTAGAAAACGGTCGTAAACGGATGCTGGCTAGTGCCGG AGAATTACAAAAAGGAAATGAGCTGGCTCTGCCAAGCAAATATGTGAATT TTTTATATTTAGCTAGTCATTATGAAAAGTTGAAGGGTAGTCCAGAAGAT AACGAACAAAAACAATTGTTTGTGGAGCAGCATAAGCATTATTTAGATGA GATTATTGAGCAAATCAGTGAATTTTCTAAGCGTGTTATTTTAGCAGATG CCAATTTAGATAAAGTTCTTAGTGCATATAACAAACATAGAGACAAACCA ATACGTGAACAAGCAGAAAATATTATTCATTTATTTACGTTGACGAATCT TGGAGCTCCCGCTGCTTTTAAATATTTTGATACAACAATTGATCGTAAAC GATATACGTCTACAAAAGAAGTTTTAGATGCCACTCTTATCCATCAATCC ATCACTGGTCTTTATGAAACACGCATTGATTTGAGTCAGCTAGGAGGTGA CTGA (SEQ ID NO: 4) MDKKYSIGLDIGTNSVGWAVITDDYKVPSKKFKVLGNTDRHSIKKNLIGA LLFGSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHR LEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLADSTDKAD LRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQIYNQLFEENP INASRVDAKAILSARLSKSRRLENLIAQLPGEKRNGLFGNLIALSLGLTP NFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKNLSDAI LLSDILRVNSEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLPEKYKEI FFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLLR KQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPY YVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDK NLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVD LLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFNASLGAYHDLLKI IKDKDFLDNEENEDILEDIVLTLTLFEDRGMIEERLKTYAHLFDDKVMKQ LKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDD SLTFKEDIQKAQVSGQGHSLHEQIANLAGSPAIKKGILQTVKIVDELVKV MGHKPENIVIEMARENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPV ENTQLQNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVPQSFIKDDS IDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLT KAERGGLSELDKAGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIR EVKVITLKSKLVSDFRKDFQFYKVREINNYHHAHDAYLNAVVGTALIKKY PKLESEFVYGDYKVYDVRKMIAKSEQEIGKATAKYFFYSNIMNFFKTEIT LANGEIRKRPLIETNGETGEIVWDKGRDFATVRKVLSMPQVNIVKKTEVQ TGGFSKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVAYSVLVVAKVEK GKSKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLPKY SLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYEKLKGSPED NEQKQLFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKHRDKP IREQAENIIHLFTLTNLGAPAAFKYFDTTIDRKRYTSTKEVLDATLIHQS ITGLYETRIDLSQLGGD  (single underline: HNH domain; double underline: RuvC domain) (single underline: HNH domain; double underline: RuvC domain)

In some embodiments, wild type Cas9 corresponds to, or comprises SEQ ID NO: 2 (nucleotide) and/or SEQ ID NO: 5 (amino acid):

(SEQ ID NO: 2) ATGGATAAAAAGTATTCTATTGGTTTAGACATCGGCACTAATTCCGTTG GATGGGCTGTCATAACCGATGAATACAAAGTACCTTCAAAGAAATTTAA GGTGTTGGGGAACACAGACCGTCATTCGATTAAAAAGAATCTTATCGGT GCCCTCCTATTCGATAGTGGCGAAACGGCAGAGGCGACTCGCCTGAAAC GAACCGCTCGGAGAAGGTATACACGTCGCAAGAACCGAATATGTTACTT ACAAGAAATTTTTAGCAATGAGATGGCCAAAGTTGACGATTCTTTCTTT CACCGTTTGGAAGAGTCCTTCCTTGTCGAAGAGGACAAGAAACATGAAC GGCACCCCATCTTTGGAAACATAGTAGATGAGGTGGCATATCATGAAAA GTACCCAACGATTTATCACCTCAGAAAAAAGCTAGTTGACTCAACTGAT AAAGCGGACCTGAGGTTAATCTACTTGGCTCTTGCCCATATGATAAAGT TCCGTGGGCACTTTCTCATTGAGGGTGATCTAAATCCGGACAACTCGGA TGTCGACAAACTGTTCATCCAGTTAGTACAAACCTATAATCAGTTGTTT GAAGAGAACCCTATAAATGCAAGTGGCGTGGATGCGAAGGCTATTCTTA GCGCCCGCCTCTCTAAATCCCGACGGCTAGAAAACCTGATCGCACAATT ACCCGGAGAGAAGAAAAATGGGTTGTTCGGTAACCTTATAGCGCTCTCA CTAGGCCTGACACCAAATTTTAAGTCGAACTTCGACTTAGCTGAAGATG CCAAATTGCAGCTTAGTAAGGACACGTACGATGACGATCTCGACAATCT ACTGGCACAAATTGGAGATCAGTATGCGGACTTATTTTTGGCTGCCAAA AACCTTAGCGATGCAATCCTCCTATCTGACATACTGAGAGTTAATACTG AGATTACCAAGGCGCCGTTATCCGCTTCAATGATCAAAAGGTACGATGA ACATCACCAAGACTTGACACTTCTCAAGGCCCTAGTCCGTCAGCAACTG CCTGAGAAATATAAGGAAATATTCTTTGATCAGTCGAAAAACGGGTACG CAGGTTATATTGACGGCGGAGCGAGTCAAGAGGAATTCTACAAGTTTAT CAAACCCATATTAGAGAAGATGGATGGGACGGAAGAGTTGCTTGTAAAA CTCAATCGCGAAGATCTACTGCGAAAGCAGCGGACTTTCGACAACGGTA GCATTCCACATCAAATCCACTTAGGCGAATTGCATGCTATACTTAGAAG GCAGGAGGATTTTTATCCGTTCCTCAAAGACAATCGTGAAAAGATTGAG AAAATCCTAACCTTTCGCATACCTTACTATGTGGGACCCCTGGCCCGAG GGAACTCTCGGTTCGCATGGATGACAAGAAAGTCCGAAGAAACGATTAC TCCATGGAATTTTGAGGAAGTTGTCGATAAAGGTGCGTCAGCTCAATCG TTCATCGAGAGGATGACCAACTTTGACAAGAATTTACCGAACGAAAAAG TATTGCCTAAGCACAGTTTACTTTACGAGTATTTCACAGTGTACAATGA ACTCACGAAAGTTAAGTATGTCACTGAGGGCATGCGTAAACCCGCCTTT CTAAGCGGAGAACAGAAGAAAGCAATAGTAGATCTGTTATTCAAGACCA ACCGCAAAGTGACAGTTAAGCAATTGAAAGAGGACTACTTTAAGAAAAT TGAATGCTTCGATTCTGTCGAGATCTCCGGGGTAGAAGATCGATTTAAT GCGTCACTTGGTACGTATCATGACCTCCTAAAGATAATTAAAGATAAGG ACTTCCTGGATAACGAAGAGAATGAAGATATCTTAGAAGATATAGTGTT GACTCTTACCCTCTTTGAAGATCGGGAAATGATTGAGGAAAGACTAAAA ACATACGCTCACCTGTTCGACGATAAGGTTATGAAACAGTTAAAGAGGC GTCGCTATACGGGCTGGGGACGATTGTCGCGGAAACTTATCAACGGGAT AAGAGACAAGCAAAGTGGTAAAACTATTCTCGATTTTCTAAAGAGCGAC GGCTTCGCCAATAGGAACTTTATGCAGCTGATCCATGATGACTCTTTAA CCTTCAAAGAGGATATACAAAAGGCACAGGTTTCCGGACAAGGGGACTC ATTGCACGAACATATTGCGAATCTTGCTGGTTCGCCAGCCATCAAAAAG GGCATACTCCAGACAGTCAAAGTAGTGGATGAGCTAGTTAAGGTCATGG GACGTCACAAACCGGAAAACATTGTAATCGAGATGGCACGCGAAAATCA AACGACTCAGAAGGGGCAAAAAAACAGTCGAGAGCGGATGAAGAGAATA GAAGAGGGTATTAAAGAACTGGGCAGCCAGATCTTAAAGGAGCATCCTG TGGAAAATACCCAATTGCAGAACGAGAAACTTTACCTCTATTACCTACA AAATGGAAGGGACATGTATGTTGATCAGGAACTGGACATAAACCGTTTA TCTGATTACGACGTCGATCACATTGTACCCCAATCCTTTTTGAAGGACG ATTCAATCGACAATAAAGTGCTTACACGCTCGGATAAGAACCGAGGGAA AAGTGACAATGTTCCAAGCGAGGAAGTCGTAAAGAAAATGAAGAACTAT TGGCGGCAGCTCCTAAATGCGAAACTGATAACGCAAAGAAAGTTCGATA ACTTAACTAAAGCTGAGAGGGGTGGCTTGTCTGAACTTGACAAGGCCGG ATTTATTAAACGTCAGCTCGTGGAAACCCGCCAAATCACAAAGCATGTT GCACAGATACTAGATTCCCGAATGAATACGAAATACGACGAGAACGATA AGCTGATTCGGGAAGTCAAAGTAATCACTTTAAAGTCAAAATTGGTGTC GGACTTCAGAAAGGATTTTCAATTCTATAAAGTTAGGGAGATAAATAAC TACCACCATGCGCACGACGCTTATCTTAATGCCGTCGTAGGGACCGCAC TCATTAAGAAATACCCGAAGCTAGAAAGTGAGTTTGTGTATGGTGATTA CAAAGTTTATGACGTCCGTAAGATGATCGCGAAAAGCGAACAGGAGATA GGCAAGGCTACAGCCAAATACTTCTTTTATTCTAACATTATGAATTTCT TTAAGACGGAAATCACTCTGGCAAACGGAGAGATACGCAAACGACCTTT AATTGAAACCAATGGGGAGACAGGTGAAATCGTATGGGATAAGGGCCGG GACTTCGCGACGGTGAGAAAAGTTTTGTCCATGCCCCAAGTCAACATAG TAAAGAAAACTGAGGTGCAGACCGGAGGGTTTTCAAAGGAATCGATTCT TCCAAAAAGGAATAGTGATAAGCTCATCGCTCGTAAAAAGGACTGGGAC CCGAAAAAGTACGGTGGCTTCGATAGCCCTACAGTTGCCTATTCTGTCC TAGTAGTGGCAAAAGTTGAGAAGGGAAAATCCAAGAAACTGAAGTCAGT CAAAGAATTATTGGGGATAACGATTATGGAGCGCTCGTCTTTTGAAAAG AACCCCATCGACTTCCTTGAGGCGAAAGGTTACAAGGAAGTAAAAAAGG ATCTCATAATTAAACTACCAAAGTATAGTCTGTTTGAGTTAGAAAATGG CCGAAAACGGATGTTGGCTAGCGCCGGAGAGCTTCAAAAGGGGAACGAA CTCGCACTACCGTCTAAATACGTGAATTTCCTGTATTTAGCGTCCCATT ACGAGAAGTTGAAAGGTTCACCTGAAGATAACGAACAGAAGCAACTTTT TGTTGAGCAGCACAAACATTATCTCGACGAAATCATAGAGCAAATTTCG GAATTCAGTAAGAGAGTCATCCTAGCTGATGCCAATCTGGACAAAGTAT TAAGCGCATACAACAAGCACAGGGATAAACCCATACGTGAGCAGGCGGA AAATATTATCCATTTGTTTACTCTTACCAACCTCGGCGCTCCAGCCGCA TTCAAGTATTTTGACACAACGATAGATCGCAAACGATACACTTCTACCA AGGAGGTGCTAGACGCGACACTGATTCACCAATCCATCACGGGATTATA TGAAACTCGGATAGATTTGTCACAGCTTGGGGGTGACGGATCCCCCAAG AAGAAGAGGAAAGTCTCGAGCGACTACAAAGACCATGACGGTGATTATA AAGATCATGACATCGATTACAAGGATGACGATGACAAGGCTGCAGGA (SEQ ID NO: 5) MDKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIG ALLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFF HRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTD KADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLF EENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALS LGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAK NLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQL PEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVK LNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIE KILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQS FIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAF LSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFN ASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLK TYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSD GFANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKK GILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRI EEGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRL SDYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNY WRQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHV AQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINN YHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEI GKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGR DFATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWD PKKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEK NPIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNE LALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQIS EFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAA FKYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD (single underline: HNH domain; double underline: RuvC domain)

In some embodiments, wild type Cas9 corresponds to Cas9 from Streptococcus pyogenes (NCBI Reference Sequence: NC_002737.2, SEQ ID NO: 3 (nucleotide); and Uniport Reference Sequence: Q99ZW2, SEQ ID NO: 6 (amino acid).

(SEQ ID NO: 3) ATGGATAAGAAATACTCAATAGGCTTAGATATCGGCACAAATAGCGTCG GATGGGCGGTGATCACTGATGAATATAAGGTTCCGTCTAAAAAGTTCAA GGTTCTGGGAAATACAGACCGCCACAGTATCAAAAAAAATCTTATAGGG GCTCTTTTATTTGACAGTGGAGAGACAGCGGAAGCGACTCGTCTCAAAC GGACAGCTCGTAGAAGGTATACACGTCGGAAGAATCGTATTTGTTATCT ACAGGAGATTTTTTCAAATGAGATGGCGAAAGTAGATGATAGTTTCTTT CATCGACTTGAAGAGTCTTTTTTGGTGGAAGAAGACAAGAAGCATGAAC GTCATCCTATTTTTGGAAATATAGTAGATGAAGTTGCTTATCATGAGAA ATATCCAACTATCTATCATCTGCGAAAAAAATTGGTAGATTCTACTGAT AAAGCGGATTTGCGCTTAATCTATTTGGCCTTAGCGCATATGATTAAGT TTCGTGGTCATTTTTTGATTGAGGGAGATTTAAATCCTGATAATAGTGA TGTGGACAAACTATTTATCCAGTTGGTACAAACCTACAATCAATTATTT GAAGAAAACCCTATTAACGCAAGTGGAGTAGATGCTAAAGCGATTCTTT CTGCACGATTGAGTAAATCAAGACGATTAGAAAATCTCATTGCTCAGCT CCCCGGTGAGAAGAAAAATGGCTTATTTGGGAATCTCATTGCTTTGTCA TTGGGTTTGACCCCTAATTTTAAATCAAATTTTGATTTGGCAGAAGATG CTAAATTACAGCTTTCAAAAGATACTTACGATGATGATTTAGATAATTT ATTGGCGCAAATTGGAGATCAATATGCTGATTTGTTTTTGGCAGCTAAG AATTTATCAGATGCTATTTTACTTTCAGATATCCTAAGAGTAAATACTG AAATAACTAAGGCTCCCCTATCAGCTTCAATGATTAAACGCTACGATGA ACATCATCAAGACTTGACTCTTTTAAAAGCTTTAGTTCGACAACAACTT CCAGAAAAGTATAAAGAAATCTTTTTTGATCAATCAAAAAACGGATATG CAGGTTATATTGATGGGGGAGCTAGCCAAGAAGAATTTTATAAATTTAT CAAACCAATTTTAGAAAAAATGGATGGTACTGAGGAATTATTGGTGAAA CTAAATCGTGAAGATTTGCTGCGCAAGCAACGGACCTTTGACAACGGCT CTATTCCCCATCAAATTCACTTGGGTGAGCTGCATGCTATTTTGAGAAG ACAAGAAGACTTTTATCCATTTTTAAAAGACAATCGTGAGAAGATTGAA AAAATCTTGACTTTTCGAATTCCTTATTATGTTGGTCCATTGGCGCGTG GCAATAGTCGTTTTGCATGGATGACTCGGAAGTCTGAAGAAACAATTAC CCCATGGAATTTTGAAGAAGTTGTCGATAAAGGTGCTTCAGCTCAATCA TTTATTGAACGCATGACAAACTTTGATAAAAATCTTCCAAATGAAAAAG TACTACCAAAACATAGTTTGCTTTATGAGTATTTTACGGTTTATAACGA ATTGACAAAGGTCAAATATGTTACTGAAGGAATGCGAAAACCAGCATTT CTTTCAGGTGAACAGAAGAAAGCCATTGTTGATTTACTCTTCAAAACAA ATCGAAAAGTAACCGTTAAGCAATTAAAAGAAGATTATTTCAAAAAAAT AGAATGTTTTGATAGTGTTGAAATTTCAGGAGTTGAAGATAGATTTAAT GCTTCATTAGGTACCTACCATGATTTGCTAAAAATTATTAAAGATAAAG ATTTTTTGGATAATGAAGAAAATGAAGATATCTTAGAGGATATTGTTTT AACATTGACCTTATTTGAAGATAGGGAGATGATTGAGGAAAGACTTAAA ACATATGCTCACCTCTTTGATGATAAGGTGATGAAACAGCTTAAACGTC GCCGTTATACTGGTTGGGGACGTTTGTCTCGAAAATTGATTAATGGTAT TAGGGATAAGCAATCTGGCAAAACAATATTAGATTTTTTGAAATCAGAT GGTTTTGCCAATCGCAATTTTATGCAGCTGATCCATGATGATAGTTTGA CATTTAAAGAAGACATTCAAAAAGCACAAGTGTCTGGACAAGGCGATAG TTTACATGAACATATTGCAAATTTAGCTGGTAGCCCTGCTATTAAAAAA GGTATTTTACAGACTGTAAAAGTTGTTGATGAATTGGTCAAAGTAATGG GGCGGCATAAGCCAGAAAATATCGTTATTGAAATGGCACGTGAAAATCA GACAACTCAAAAGGGCCAGAAAAATTCGCGAGAGCGTATGAAACGAATC GAAGAAGGTATCAAAGAATTAGGAAGTCAGATTCTTAAAGAGCATCCTG TTGAAAATACTCAATTGCAAAATGAAAAGCTCTATCTCTATTATCTCCA AAATGGAAGAGACATGTATGTGGACCAAGAATTAGATATTAATCGTTTA AGTGATTATGATGTCGATCACATTGTTCCACAAAGTTTCCTTAAAGACG ATTCAATAGACAATAAGGTCTTAACGCGTTCTGATAAAAATCGTGGTAA ATCGGATAACGTTCCAAGTGAAGAAGTAGTCAAAAAGATGAAAAACTAT TGGAGACAACTTCTAAACGCCAAGTTAATCACTCAACGTAAGTTTGATA ATTTAACGAAAGCTGAACGTGGAGGTTTGAGTGAACTTGATAAAGCTGG TTTTATCAAACGCCAATTGGTTGAAACTCGCCAAATCACTAAGCATGTG GCACAAATTTTGGATAGTCGCATGAATACTAAATACGATGAAAATGATA AACTTATTCGAGAGGTTAAAGTGATTACCTTAAAATCTAAATTAGTTTC TGACTTCCGAAAAGATTTCCAATTCTATAAAGTACGTGAGATTAACAAT TACCATCATGCCCATGATGCGTATCTAAATGCCGTCGTTGGAACTGCTT TGATTAAGAAATATCCAAAACTTGAATCGGAGTTTGTCTATGGTGATTA TAAAGTTTATGATGTTCGTAAAATGATTGCTAAGTCTGAGCAAGAAATA GGCAAAGCAACCGCAAAATATTTCTTTTACTCTAATATCATGAACTTCT TCAAAACAGAAATTACACTTGCAAATGGAGAGATTCGCAAACGCCCTCT AATCGAAACTAATGGGGAAACTGGAGAAATTGTCTGGGATAAAGGGCGA GATTTTGCCACAGTGCGCAAAGTATTGTCCATGCCCCAAGTCAATATTG TCAAGAAAACAGAAGTACAGACAGGCGGATTCTCCAAGGAGTCAATTTT ACCAAAAAGAAATTCGGACAAGCTTATTGCTCGTAAAAAAGACTGGGAT CCAAAAAAATATGGTGGTTTTGATAGTCCAACGGTAGCTTATTCAGTCC TAGTGGTTGCTAAGGTGGAAAAAGGGAAATCGAAGAAGTTAAAATCCGT TAAAGAGTTACTAGGGATCACAATTATGGAAAGAAGTTCCTTTGAAAAA AATCCGATTGACTTTTTAGAAGCTAAAGGATATAAGGAAGTTAAAAAAG ACTTAATCATTAAACTACCTAAATATAGTCTTTTTGAGTTAGAAAACGG TCGTAAACGGATGCTGGCTAGTGCCGGAGAATTACAAAAAGGAAATGAG CTGGCTCTGCCAAGCAAATATGTGAATTTTTTATATTTAGCTAGTCATT ATGAAAAGTTGAAGGGTAGTCCAGAAGATAACGAACAAAAACAATTGTT TGTGGAGCAGCATAAGCATTATTTAGATGAGATTATTGAGCAAATCAGT GAATTTTCTAAGCGTGTTATTTTAGCAGATGCCAATTTAGATAAAGTTC TTAGTGCATATAACAAACATAGAGACAAACCAATACGTGAACAAGCAGA AAATATTATTCATTTATTTACGTTGACGAATCTTGGAGCTCCCGCTGCT TTTAAATATTTTGATACAACAATTGATCGTAAACGATATACGTCTACAA AAGAAGTTTTAGATGCCACTCTTATCCATCAATCCATCACTGGTCTTTA TGAAACACGCATTGATTTGAGTCAGCTAGGAGGTGACTGA (SEQ ID NO: 6) MDKKYSIGLDIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIG ALLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFF HRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTD KADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLF EENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALS LGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAK NLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQL PEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVK LNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIE KILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQS FIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAF LSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFN ASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLK TYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSD GFANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKK GILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRI EEGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRL SDYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNY WRQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHV AQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINN YHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEI GKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGR DFATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWD PKKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEK NPIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNE LALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQIS EFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAA FKYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD (single underline: HNH domain; double underline: RuvC domain)

In some embodiments, Cas9 refers to Cas9 from: Corynebacterium ulcerans (NCBI Refs: NC_015683.1, NC_017317.1); Corynebacterium diphtheria (NCBI Refs: NC_016782.1, NC_016786.1); Spiroplasma syrphidicola (NCBI Ref: NC_021284.1); Prevotella intermedia (NCBI Ref: NC_017861.1); Spiroplasma taiwanense (NCBI Ref: NC_021846.1); Streptococcus iniae (NCBI Ref: NC_021314.1); Belliella baltica (NCBI Ref: NC_018010.1); Psychroflexus torquisl (NCBI Ref: NC_018721.1); Streptococcus thermophilus (NCBI Ref: YP_820832.1), Listeria innocua (NCBI Ref: NP_472073.1), Campylobacter jejuni (NCBI Ref: YP_002344900.1) or Neisseria. meningitidis (NCBI Ref: YP_002342100.1) or to a Cas9 from any other organism.

In some embodiments, dCas9 corresponds to, or comprises in part or in whole, a Cas9 amino acid sequence having one or more mutations that inactivate the Cas9 nuclease activity. For example, in some embodiments, a dCas9 domain comprises D10A and an H840A mutation of SEQ ID NO: 6 or corresponding mutations in another Cas9. In some embodiments, the dCas9 comprises the amino acid sequence of SEQ ID NO: 7 dCas9 (D10A and H840A):

(SEQ ID NO: 7) MDKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIG ALLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFF HRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTD KADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLF EENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALS LGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAK NLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQL PEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVK LNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIE KILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQS FIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAF LSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFN ASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLK TYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSD GFANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKK GILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQK NSRERMKRI EEGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRL SDYDVDAIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNY WRQLLNAKLITQRKFDNLTKAERGGLS ELDKAGFIKRQLVETRQITKHV AQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINN YHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEI GKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGR DFATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWD PKKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEK NPIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNE LALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQIS EFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAA FKYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD (single underline: HNH domain; double underline: RuvC domain).

In some embodiments, the Cas9 domain comprises a D10A mutation, while the residue at position 840 remains a histidine in the amino acid sequence provided in SEQ ID NO: 6, or at corresponding positions in another Cas9, such as a Cas9 set forth in any of the amino acid sequences provided in SEQ ID NOs: 4-26. Without wishing to be bound by any particular theory, the presence of the catalytic residue H840 maintains the activity of the Cas9 to cleave the non-edited (e.g., non-deaminated) strand containing a T opposite the targeted A. Restoration of H840 (e.g., from A840 of a dCas9) does not result in the cleavage of the target strand containing the A. Such Cas9 variants are able to generate a single-strand DNA break (nick) at a specific location based on the gRNA-defined target sequence, leading to repair of the non-edited strand, ultimately resulting in a T to C change on the non-edited strand.

In other embodiments, dCas9 variants having mutations other than D10A and H840A are provided, which, e.g., result in nuclease inactivated Cas9 (dCas9). Such mutations, by way of example, include other amino acid substitutions at D10 and H840, or other substitutions within the nuclease domains of Cas9 (e.g., substitutions in the HNH nuclease subdomain and/or the RuvC1 subdomain). In some embodiments, variants or homologues of dCas9 (e.g., variants of SEQ ID NO: 6, 7, 8, 9, or 22) are provided which are at least about 70% identical, at least about 80% identical, at least about 90% identical, at least about 95% identical, at least about 98% identical, at least about 99% identical, at least about 99.5% identical, or at least about 99.9% identical to SEQ ID NO: 6, 7, 8, 9, or 22. In some embodiments, variants of dCas9 (e.g., variants of SEQ ID NO: 6, 7, 8, 9, or 22) are provided having amino acid sequences which are shorter, or longer than SEQ ID NO: 7, 8, 9, or 22, by about 5 amino acids, by about 10 amino acids, by about 15 amino acids, by about 20 amino acids, by about 25 amino acids, by about 30 amino acids, by about 40 amino acids, by about 50 amino acids, by about 75 amino acids, by about 100 amino acids or more.

In some embodiments, Cas9 fusion proteins as provided herein comprise the full-length amino acid sequence of a Cas9 protein, e.g., one of the Cas9 sequences provided herein. In other embodiments, however, fusion proteins as provided herein do not comprise a full-length Cas9 sequence, but only a fragment thereof. For example, in some embodiments, a Cas9 fusion protein provided herein comprises a Cas9 fragment, wherein the fragment binds crRNA and tracrRNA or sgRNA, but does not comprise a functional nuclease domain, e.g., in that it comprises only a truncated version of a nuclease domain or no nuclease domain at all.

Exemplary amino acid sequences of suitable Cas9 domains and Cas9 fragments are provided herein, and additional suitable sequences of Cas9 domains and fragments will be apparent to those of skill in the art.

In some embodiments, Cas9 refers to Cas9 from: Corynebacterium ulcerans (NCBI Refs: NC_015683.1, NC_017317.1); Corynebacterium diphtheria (NCBI Refs: NC_016782.1, NC_016786.1); Spiroplasma syrphidicola (NCBI Ref: NC_021284.1); Prevotella intermedia (NCBI Ref: NC_017861.1); Spiroplasma taiwanense (NCBI Ref: NC_021846.1); Streptococcus iniae (NCBI Ref: NC_021314.1); Belliella baltica (NCBI Ref: NC_018010.1); Psychroflexus torquisl (NCBI Ref: NC_018721.1); Streptococcus thermophilus (NCBI Ref: YP_820832.1); Listeria innocua (NCBI Ref: NP_472073.1); Campylobacter jejuni (NCBI Ref: YP_002344900.1); or Neisseria. meningitidis (NCBI Ref: YP_002342100.1).

It should be appreciated that additional Cas9 proteins (e.g., a nuclease dead Cas9 (dCas9), a Cas9 nickase (nCas9), or a nuclease active Cas9), including variants and homologs thereof, are within the scope of this disclosure. Exemplary Cas9 proteins include, without limitation, those provided below. In some embodiments, the Cas9 protein is a nuclease dead Cas9 (dCas9). In some embodiments, the dCas9 comprises the amino acid sequence (SEQ ID NO: 7, 8, 9, or 22). In some embodiments, the Cas9 protein is a Cas9 nickase (nCas9). In some embodiments, the nCas9 comprises the amino acid sequence (SEQ ID NO: 10, 13, 16, or 21). In some embodiments, the Cas9 protein is a nuclease active Cas9. In some embodiments, the nuclease active Cas9 comprises the amino acid sequence (SEQ ID NO: 4, 5, 6, 11, 12, 14, 15, 16, 17, 18, 19, 20, 23, 24, 25, or 26).

Exemplary catalytically inactive Cas9 (dCas9): (SEQ ID NO: 8) DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGA LLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFH RLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDK ADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFE ENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSL GLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKN LSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLP EKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKL NREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEK ILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSF IERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVETSGVEDRFNA SLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKT YAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDG FANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKG ILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIE EGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLS DYDVDAIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYW RQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVA QILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNY HHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIG KATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRD FATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDP KKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKN PIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNEL ALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAF KYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD Exemplary Cas9 nickase (nCas9): (SEQ ID NO: 10) DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGA LLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFH RLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDK ADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFE ENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSL GLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKN LSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLP EKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKL NREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEK ILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSF IERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVETSGVEDRFNA SLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKT YAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDG FANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKG ILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIE EGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLS DYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYW RQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVA QILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNY HHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIG KATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRD FATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDP KKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKN PIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNEL ALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAF KYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD Exemplary catalytically active Cas9: (SEQ ID NO: 11)  DKKYSIGLDIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGA LLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFH RLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDK ADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFE ENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSL GLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKN LSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLP EKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKL NREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEK ILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSF IERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVETSGVEDRFNA SLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKT YAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDG FANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKG ILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIE EGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLS DYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYW RQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVA QILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNY HHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIG KATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRD FATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDP KKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKN PIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNEL ALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAF KYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD

The term “Cas9 nickase,” as used herein, refers to a Cas9 protein that is capable of cleaving only one strand of a duplexed nucleic acid molecule (e.g., a duplexed DNA molecule). In some embodiments, a Cas9 nickase comprises a D10A mutation and has a histidine at position H840 of SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided, such as any one of SEQ ID NOs: 4-26. For example, a Cas9 nickase may comprise the amino acid sequence as set forth in SEQ ID NO: 10, 13, 16, or 21. Such a Cas9 nickase has an active HNH nuclease domain and is able to cleave the non-targeted strand of DNA, i.e., the strand bound by the gRNA. Further, such a Cas9 nickase has an inactive RuvC nuclease domain and is not able to cleave the targeted strand of the DNA, i.e., the strand where base editing is desired.

In some embodiments, Cas9 refers to a Cas9 from arehaea (e.g. nanoarchaea), which constitute a domain and kingdom of single-celled prokaryotic microbes. In some embodiments, Cas9 refers to CasX or CasY, which have been described in, for example, Burstein et al., “New CRISPR-Cas systems from uncultivated microbes.” Cell Res. 2017 Feb. 21. doi: 10.1038/cr.2017.21, the entire contents of which is hereby incorporated by reference. Using genome-resolved metagenomics, a number of CRISPR-Cas systems were identified, including the first reported Cas9 in the archaeal domain of life. This divergent Cas9 protein was found in little-studied nanoarchaea as part of an active CRISPR-Cas system. In bacteria, two previously unknown systems were discovered, CRISPR-CasX and CRISPR-CasY, which are among the most compact systems yet discovered. In some embodiments, Cas9 refers to CasX, or a variant of CasX. In some embodiments, Cas9 refers to a CasY, or a variant of CasY. It should be appreciated that other RNA-guided DNA binding proteins may be used as a nucleic acid programmable DNA binding protein (napDNAbp), and are within the scope of this disclosure.

In some embodiments, the nucleic acid programmable DNA binding protein (napDNAbp) of any of the fusion proteins provided herein may be a CasX or CasY protein. In some embodiments, the napDNAbp is a CasX protein. In some embodiments, the CasX protein is a nuclease inactive CasX protein (dCasX), a CasX nickase (CasXn), or a nuclease active CasX. In some embodiments, the napDNAbp is a CasY protein. In some embodiments, the CasY protein is a nuclease inactive CasY protein (dCasY), a CasY nickase (CasYn), or a nuclease active CasY. In some embodiments, the napDNAbp comprises an amino acid sequence that is at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at ease 99.5% identical to a naturally-occurring CasX or CasY protein. In some embodiments, the napDNAbp is a naturally-occurring CasX or CasY protein. In some embodiments, the napDNAbp comprises an amino acid sequence that is at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at ease 99.5% identical to any one of SEQ ID NOs: 27-29. In some embodiments, the napDNAbp comprises an amino acid sequence of any one SEQ ID NOs: 27-29. It should be appreciated that CasX and CasY from other bacterial species may also be used in accordance with the present disclosure.

CasX (uniprot.org/uniprot/F0NN87; uniprot.org/uniprot/F0NH53) >tr|F0NN87|F0NN87_SULIH CRISPR-associated Casx protein OS = Sulfolobus islandicus (strain HVE10/4) GN = SiH_0402 PE = 4 SV = 1 (SEQ ID NO: 27) MEVPLYNIFGDNYIIQVATEAENSTIYNNKVEIDDEELRNVLNLAYKIAKNNEDAAAE RRGKAKKKKGEEGETTTSNIILPLSGNDKNPWTETLKCYNFPTTVALSEVFKNFSQV KECEEVSAPSFVKPEFYEFGRSPGMVERTRRVKLEVEPHYLIIAAAGWVLTRLGKAK VSEGDYVGVNVFTPTRGILYSLIQNVNGIVPGIKPETAFGLWIARKVVSSVTNPNVSV VRIYTISDAVGQNPTTINGGFSIDLTKLLEKRYLLSERLEAIARNALSISSNMRERYIVL ANYIYEYLTGSKRLEDLLYFANRDLIMNLNSDDGKVRDLKLISAYVNGELIRGEG >tr|F0NH53|F0NH53_SULIR CRISPR associated protein, Casx OS = Sulfolobus islandicus (strain REY15A) GN = SiRe_0771 PE = 4 SV = 1 (SEQ ID NO: 28) MEVPLYNIFGDNYIIQVATEAENSTIYNNKVEIDDEELRNVLNLAYKIAKNNEDAAAE RRGKAKKKKGEEGETTTSNIILPLSGNDKNPWTETLKCYNFPTTVALSEVFKNFSQV KECEEVSAPSFVKPEFYKFGRSPGMVERTRRVKLEVEPHYLIMAAAGWVLTRLGKA KVSEGDYVGVNVFTPTRGILYSLIQNVNGIVPGIKPETAFGLWIARKVVSSVTNPNVS VVSIYTISDAVGQNPTTINGGFSIDLTKLLEKRDLLSERLEAIARNALSISSNMRERYIV LANYIYEYLTGSKRLEDLLYFANRDLIMNLNSDDGKVRDLKLISAYVNGELIRGEG CasY (ncbi.nlm.nih.gov/protein/APG80656.1) >APG80656.1 CRISPR-associated protein CasY [uncultured Parcubacteria group bacterium] (SEQ ID NO: 29) MSKRHPRISGVKGYRLHAQRLEYTGKSGAMRTIKYPLYSSPSGGRTVPREIVSAINDD YVGLYGLSNFDDLYNAEKRNEEKVYSVLDFWYDCVQYGAVFSYTAPGLLKNVAEV RGGSYELTKTLKGSHLYDELQIDKVIKFLNKKEISRANGSLDKLKKDIIDCFKAEYRE RHKDQCNKLADDIKNAKKDAGASLGERQKKLFRDFFGISEQSENDKPSFTNPLNLTC CLLPFDTVNNNRNRGEVLFNKLKEYAQKLDKNEGSLEMWEYIGIGNSGTAFSNFLGE GFLGRLRENKITELKKAMMDITDAWRGQEQEEELEKRLRILAALTIKLREPKFDNHW GGYRSDINGKLSSWLQNYINQTVKIKEDLKGHKKDLKKAKEMINRFGESDTKEEAV VSSLLESIEKIVPDDSADDEKPDIPAIAIYRRFLSDGRLTLNRFVQREDVQEALIKERLE AEKKKKPKKRKKKSDAEDEKETIDFKELFPHLAKPLKLVPNFYGDSKRELYKKYKN AAIYTDALWKAVEKIYKSAFSSSLKNSFFDTDFDKDFFIKRLQKIFSVYRRFNTDKWK PIVKNSFAPYCDIVSLAENEVLYKPKQSRSRKSAAIDKNRVRLPSTENIAKAGIALARE LSVAGFDWKDLLKKEEHEEYIDLIELHKTALALLLAVTETQLDISALDFVENGTVKD FMKTRDGNLVLEGRFLEMFSQSIVFSELRGLAGLMSRKEFITRSAIQTMNGKQAELL YIPHEFQSAKITTPKEMSRAFLDLAPAEFATSLEPESLSEKSLLKLKQMRYYPHYFGY ELTRTGQGIDGGVAENALRLEKSPVKKREIKCKQYKTLGRGQNKIVLYVRSSYYQTQ FLEWFLHRPKNVQTDVAVSGSFLIDEKKVKTRWNYDALTVALEPVSGSERVFVSQPF TIFPEKSAEEEGQRYLGIDIGEYGIAYTALEITGDSAKILDQNFISDPQLKTLREEVKGL KLDQRRGTFAMPSTKIARIRESLVHSLRNRIHHLALKHKAKIVYELEVSRFEEGKQKI KKVYATLKKADVYSEIDADKNLQTTVWGKLAVASEISASYTSQFCGACKKLWRAE MQVDETITTQELIGTVRVIKGGTLIDAIKDFMRPPIFDENDTPFPKYRDFCDKHHISKK MRGNSCLFICPFCRANADADIQASQTIALLRYVKEEKKVEDYFERFRKLKNIKVLGQ MKKI

The term “effective amount,” as used herein, refers to an amount of a biologically active agent that is sufficient to elicit a desired biological response. For example, in some embodiments, an effective amount of a nucleobase editor may refer to the amount of the nucleobase editor that is sufficient to induce a mutation of a target site specifically bound by the nucleobase editor. In some embodiments, an effective amount of a fusion protein provided herein, e.g., of a fusion protein comprising a nucleic acid programmable DNA binding protein and a deaminase domain (e.g., a cytidine deaminase domain) may refer to the amount of the fusion protein that is sufficient to induce editing of a target site specifically bound and edited by the fusion protein. As will be appreciated by the skilled artisan, the effective amount of an agent, e.g., a fusion protein, a nucleobase editor, a deaminase, a hybrid protein, a protein dimer, a complex of a protein (or protein dimer) and a polynucleotide, or a polynucleotide, may vary depending on various factors as, for example, on the desired biological response, e.g., on the specific allele, genome, or target site to be edited, on the cell or tissue being targeted, and on the agent being used.

The terms “nucleic acid” and “nucleic acid molecule,” as used herein, refer to a compound comprising a nucleobase and an acidic moiety, e.g., a nucleoside, a nucleotide, or a polymer of nucleotides. Typically, polymeric nucleic acids, e.g., nucleic acid molecules comprising three or more nucleotides are linear molecules, in which adjacent nucleotides are linked to each other via a phosphodiester linkage. In some embodiments, “nucleic acid” refers to individual nucleic acid residues (e.g. nucleotides and/or nucleosides). In some embodiments, “nucleic acid” refers to an oligonucleotide chain comprising three or more individual nucleotide residues. As used herein, the terms “oligonucleotide” and “polynucleotide” can be used interchangeably to refer to a polymer of nucleotides (e.g., a string of at least three nucleotides). In some embodiments, “nucleic acid” encompasses RNA as well as single and/or double-stranded DNA. Nucleic acids may be naturally occurring, for example, in the context of a genome, a transcript, an mRNA, tRNA, rRNA, siRNA, snRNA, a plasmid, cosmid, chromosome, chromatid, or other naturally occurring nucleic acid molecule. On the other hand, a nucleic acid molecule may be a non-naturally occurring molecule, e.g., a recombinant DNA or RNA, an artificial chromosome, an engineered genome, or fragment thereof, or a synthetic DNA, RNA, DNA/RNA hybrid, or including non-naturally occurring nucleotides or nucleosides. Furthermore, the terms “nucleic acid,” “DNA,” “RNA,” and/or similar terms include nucleic acid analogs, e.g., analogs having other than a phosphodiester backbone. Nucleic acids can be purified from natural sources, produced using recombinant expression systems and optionally purified, chemically synthesized, etc. Where appropriate, e.g., in the case of chemically synthesized molecules, nucleic acids can comprise nucleoside analogs such as analogs having chemically modified bases or sugars, and backbone modifications. A nucleic acid sequence is presented in the 5′ to 3′ direction unless otherwise indicated. In some embodiments, a nucleic acid is or comprises natural nucleosides (e.g. adenosine, thymidine, guanosine, cytidine, uridine, deoxyadenosine, deoxythymidine, deoxyguanosine, and deoxycytidine); nucleoside analogs (e.g., 2-aminoadenosine, 2-thiothymidine, inosine, pyrrolo-pyrimidine, 3-methyl adenosine, 5-methylcytidine, 2-aminoadenosine, C5-bromouridine, C5-fluorouridine, C5-iodouridine, C5-propynyl-uridine, C5-propynyl-cytidine, C5-methylcytidine, 2-aminoadenosine, 7-deazaadenosine, 7-deazaguanosine, 8-oxoadenosine, 8-oxoguanosine, 0(6)-methylguanine, and 2-thiocytidine); chemically modified bases; biologically modified bases (e.g., methylated bases); intercalated bases; modified sugars (e.g., 2′-fluororibose, ribose, 2′-deoxyribose, arabinose, and hexose); and/or modified phosphate groups (e.g., phosphorothioates and 5′-N-phosphoramidite linkages).

The term “proliferative disease,” as used herein, refers to any disease in which cell or tissue homeostasis is disturbed in that a cell or cell population exhibits an abnormally elevated proliferation rate. Proliferative diseases include hyperproliferative diseases, such as pre-neoplastic hyperplastic conditions and neoplastic diseases. Neoplastic diseases are characterized by an abnormal proliferation of cells and include both benign and malignant neoplasias. Malignant neoplasia is also referred to as cancer.

The terms “protein,” “peptide,” and “polypeptide” are used interchangeably herein, and refer to a polymer of amino acid residues linked together by peptide (amide) bonds. The terms refer to a protein, peptide, or polypeptide of any size, structure, or function. Typically, a protein, peptide, or polypeptide will be at least three amino acids long. A protein, peptide, or polypeptide may refer to an individual protein or a collection of proteins. One or more of the amino acids in a protein, peptide, or polypeptide may be modified, for example, by the addition of a chemical entity such as a carbohydrate group, a hydroxyl group, a phosphate group, a farnesyl group, an isofarnesyl group, a fatty acid group, a linker for conjugation, functionalization, or other modification, etc. A protein, peptide, or polypeptide may also be a single molecule or may be a multi-molecular complex. A protein, peptide, or polypeptide may be just a fragment of a naturally occurring protein or peptide. A protein, peptide, or polypeptide may be naturally occurring, recombinant, or synthetic, or any combination thereof.

The term “fusion protein” as used herein refers to a hybrid polypeptide which comprises protein domains from at least two different proteins. One protein may be located at the amino-terminal (N-terminal) portion of the fusion protein or at the carboxy-terminal (C-terminal) protein thus forming an “amino-terminal fusion protein” or a “carboxy-terminal fusion protein,” respectively. A protein may comprise different domains, for example, a nucleic acid binding domain (e.g., the gRNA binding domain of Cas9 that directs the binding of the protein to a target site) and a nucleic acid cleavage domain or a catalytic domain of a nucleic-acid editing protein. In some embodiments, a protein comprises a proteinaceous part, e.g., an amino acid sequence constituting a nucleic acid binding domain, and an organic compound, e.g., a compound that can act as a nucleic acid cleavage agent. In some embodiments, a protein is in a complex with, or is in association with, a nucleic acid, e.g., RNA. Any of the proteins provided herein may be produced by any method known in the art. For example, the proteins provided herein may be produced via recombinant protein expression and purification, which is especially suited for fusion proteins comprising a peptide linker. Methods for recombinant protein expression and purification are well known, and include those described by Green and Sambrook, Molecular Cloning: A Laboratory Manual (4^(th) ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (2012)), the entire contents of which are incorporated herein by reference.

The term “RNA-programmable nuclease,” and “RNA-guided nuclease” are used interchangeably herein and refer to a nuclease that forms a complex with (e.g., binds or associates with) one or more RNA(s) that is not a target for cleavage. In some embodiments, an RNA-programmable nuclease, when in a complex with an RNA, may be referred to as a nuclease:RNA complex. Typically, the bound RNA(s) is referred to as a guide RNA (gRNA). gRNAs can exist as a complex of two or more RNAs, or as a single RNA molecule. gRNAs that exist as a single RNA molecule may be referred to as single-guide RNAs (sgRNAs), though “gRNA” is used interchangeably to refer to guide RNAs that exist as either single molecules or as a complex of two or more molecules. Typically, gRNAs that exist as single RNA species comprise two domains: (1) a domain that shares homology to a target nucleic acid (e.g., and directs binding of a Cas9 complex to the target); and (2) a domain that binds a Cas9 protein. In some embodiments, domain (2) corresponds to a sequence known as a tracrRNA, and comprises a stem-loop structure. For example, in some embodiments, domain (2) is identical or homologous to a tracrRNA as provided in Jinek et al., Science 337:816-821(2012), the entire contents of which is incorporated herein by reference. Other examples of gRNAs (e.g., those including domain 2) can be found in U.S. Provisional Patent Application, U.S. Ser. No. 61/874,682, filed Sep. 6, 2013, entitled “Switchable Cas9 Nucleases And Uses Thereof,” and U.S. Provisional Patent Application, U.S. Ser. No. 61/874,746, filed Sep. 6, 2013, entitled “Delivery System For Functional Nucleases,” the entire contents of each are hereby incorporated by reference in their entirety. In some embodiments, a gRNA comprises two or more of domains (1) and (2), and may be referred to as an “extended gRNA.” For example, an extended gRNA will, e.g., bind two or more Cas9 proteins and bind a target nucleic acid at two or more distinct regions, as described herein. The gRNA comprises a nucleotide sequence that complements a target site, which mediates binding of the nuclease/RNA complex to said target site, providing the sequence specificity of the nuclease:RNA complex. In some embodiments, the RNA-programmable nuclease is the (CRISPR-associated system) Cas9 endonuclease, for example, Cas9 (Csnl) from Streptococcus pyogenes (see, e.g., “Complete genome sequence of an M1 strain of Streptococcus pyogenes.” Ferretti J. J., McShan W. M., Ajdic D. J., Savic D. J., Savic G., Lyon K., Primeaux C., Sezate S., Suvorov A. N., Kenton S., Lai H. S., Lin S. P., Qian Y., Jia H. G., Najar F. Z., Ren Q., Zhu H., Song L., White J., Yuan X., Clifton S. W., Roe B. A., McLaughlin R. E., Proc. Natl. Acad. Sci. U.S.A. 98:4658-4663(2001); “CRISPR RNA maturation by trans-encoded small RNA and host factor RNase III.” Deltcheva E., Chylinski K., Sharma C. M., Gonzales K., Chao Y., Pirzada Z. A., Eckert M. R., Vogel J., Charpentier E., Nature 471:602-607(2011); and “A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity.” Jinek M., Chylinski K., Fonfara I., Hauer M., Doudna J. A., Charpentier E. Science 337:816-821(2012), the entire contents of each of which are incorporated herein by reference.

Because RNA-programmable nucleases (e.g., Cas9) use RNA:DNA hybridization to target DNA cleavage sites, these proteins are able to be targeted, in principle, to any sequence specified by the guide RNA. Methods of using RNA-programmable nucleases, such as Cas9, for site-specific cleavage (e.g., to modify a genome) are known in the art (see e.g., Cong, L. et al., Multiplex genome engineering using CRISPR/Cas systems. Science 339, 819-823 (2013); Mali, P. et al., RNA-guided human genome engineering via Cas9. Science 339, 823-826 (2013); Hwang, W. Y. et al., Efficient genome editing in zebrafish using a CRISPR-Cas system. Nature biotechnology 31, 227-229 (2013); Jinek, M. et al., RNA-programmed genome editing in human cells. eLife 2, e00471 (2013); Dicarlo, J. E. et al., Genome engineering in Saccharomyces cerevisiae using CRISPR-Cas systems. Nucleic acids research (2013); Jiang, W. et al. RNA-guided editing of bacterial genomes using CRISPR-Cas systems. Nature biotechnology 31, 233-239 (2013); the entire contents of each of which are incorporated herein by reference).

The term “subject,” as used herein, refers to an individual organism, for example, an individual mammal. In some embodiments, the subject is a human. In some embodiments, the subject is a non-human mammal. In some embodiments, the subject is a non-human primate. In some embodiments, the subject is a rodent. In some embodiments, the subject is a sheep, a goat, a cattle, a cat, or a dog. In some embodiments, the subject is a vertebrate, an amphibian, a reptile, a fish, an insect, a fly, or a nematode. In some embodiments, the subject is a research animal. In some embodiments, the subject is genetically engineered, e.g., a genetically engineered non-human subject. The subject may be of either sex and at any stage of development.

The term “target site” refers to a sequence within a nucleic acid molecule that is modified by a base editor, such as a fusion protein comprising a cytidine deaminase, (e.g., a dCas9-cytidine deaminase fusion protein provided herein).

The terms “treatment,” “treat,” and “treating,” refer to a clinical intervention aimed to reverse, alleviate, delay the onset of, or inhibit the progress of a disease or disorder, or one or more symptoms thereof, as described herein. As used herein, the terms “treatment,” “treat,” and “treating” refer to a clinical intervention aimed to reverse, alleviate, delay the onset of, or inhibit the progress of a disease or disorder, or one or more symptoms thereof, as described herein. In some embodiments, treatment may be administered after one or more symptoms have developed and/or after a disease has been diagnosed. In other embodiments, treatment may be administered in the absence of symptoms, e.g., to prevent or delay onset of a symptom or inhibit onset or progression of a disease. For example, treatment may be administered to a susceptible individual prior to the onset of symptoms (e.g., in light of a history of symptoms and/or in light of genetic or other susceptibility factors). Treatment may also be continued after symptoms have resolved, for example, to prevent or delay their recurrence.

The term “recombinant” as used herein in the context of proteins or nucleic acids refers to proteins or nucleic acids that do not occur in nature, but are the product of human engineering. For example, in some embodiments, a recombinant protein or nucleic acid molecule comprises an amino acid or nucleotide sequence that comprises at least one, at least two, at least three, at least four, at least five, at least six, or at least seven mutations as compared to any naturally occurring sequence.

DETAILED DESCRIPTION OF INVENTION

Nucleic Acid Programmable DNA Binding Proteins (napDNAbp)

Some aspects of the disclosure provide nucleic acid programmable DNA binding proteins, which may be used to guide a protein, such as a base editor, to a specific nucleic acid (e.g., DNA or RNA) sequence. Nucleic acid programmable DNA binding proteins include, without limitation, Cas9 (e.g., dCas9 and nCas9), CasX, CasY, Cpf1, C2c1, C2c2, C2C3, and Argonaute. One example of a nucleic acid programmable DNA-binding protein that has different PAM specificity than Cas9 is Clustered Regularly Interspaced Short Palindromic Repeats from Prevotella and Francisella 1 (Cpf1). Similar to Cas9, Cpf1 is also a class 2 CRISPR effector. It has been shown that Cpf1 mediates robust DNA interference with features distinct from Cas9. Cpf1 is a single RNA-guided endonuclease lacking tracrRNA, and it utilizes a T-rich protospacer-adjacent motif (TTN, TTTN, or YTN). Moreover, Cpf1 cleaves DNA via a staggered DNA double-stranded break. Out of 16 Cpf1-family proteins, two enzymes from Acidaminococcus and Lachnospiraceae are shown to have efficient genome-editing activity in human cells. Cpf1 proteins are known in the art and have been described previously, for example Yamano et al., “Crystal structure of Cpf1 in complex with guide RNA and target DNA.” Cell (165) 2016, p. 949-962; the entire contents of which is hereby incorporated by reference.

Also useful in the present compositions and methods are nuclease-inactive Cpf1 (dCpf1) variants that may be used as a guide nucleotide sequence-programmable DNA-binding protein domain. The Cpf1 protein has a RuvC-like endonuclease domain that is similar to the RuvC domain of Cas9 but does not have a HNH endonuclease domain, and the N-terminal of Cpf1 does not have the alfa-helical recognition lobe of Cas9. It was shown in Zetsche et al., Cell, 163, 759-771, 2015 (which is incorporated herein by reference) that, the RuvC-like domain of Cpf1 is responsible for cleaving both DNA strands and inactivation of the RuvC-like domain inactivates Cpf1 nuclease activity. For example, mutations corresponding to D917A, E1006A, or D1255A in Francisella novicida Cpf1 (SEQ ID NO: 30) inactivates Cpf1 nuclease activity. In some embodiments, the dCpf1 of the present disclosure comprises mutations corresponding to D917A, E1006A, D1255A, D917A/E1006A, D917A/D1255A, E1006A/D1255A, or D917A/E1006A/D1255A in SEQ ID NO: 30, or corresponding mutation(s) in another Cpf1. It is to be understood that any mutations, e.g., substitution mutations, deletions, or insertions that inactivate the RuvC domain of Cpf1, may be used in accordance with the present disclosure.

In some embodiments, the nucleic acid programmable DNA binding protein (napDNAbp) of any of the fusion proteins provided herein may be a Cpf1 protein. In some embodiments, the Cpf1 protein is a Cpf1 nickase (nCpf1). In some embodiments, the Cpf1 protein is a nuclease inactive Cpf1 (dCpf1). In some embodiments, the Cpf1, the nCpf1, or the dCpf1 comprises an amino acid sequence that is at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at ease 99.5% identical to any one of SEQ ID NOs: 30-37. In some embodiments, the dCpf1 comprises an amino acid sequence that is at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at ease 99.5% identical to any one of SEQ ID NOs: 30-37, and comprises mutations corresponding to D917A, E1006A, D1255A, D917A/E1006A, D917A/D1255A, E1006A/D1255A, and or D917A/E1006A/D1255A in SEQ ID NO: 30 or corresponding mutation(s) inahother Cpf1. In some embodiments, the dCpf1 comprises an amino acid sequence of any one SEQ ID NOs: 30-37. It should be appreciated that Cpf1 from other bacterial species may also be used in accordance with the present disclosure.

Wild type Francisella novicida Cpf1 (SEQ ID NO: 30) (D917, E1006, and D1255 are bolded and underlined) (SEQ ID NO: 30) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSITYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI D RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF E DLNFGFKRGRFKVEKQVYQKLEKMLIEKLN YLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFVN QLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGSR LINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAKLT SVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA D ANGAYHIGL KGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 D917A (SEQ ID NO: 31) (A917, E1006, and D1255 are bolded and underlined) (SEQ ID NO: 31) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSITYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI A RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF E DLNFGFKRGRFKVEKQVYQKLEKMLIEKLN YLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFVN QLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGSR LINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAKLT SVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA D ANGAYHIGL KGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 E1006A (SEQ ID NO: 32) (D917, A1006, and D1255 are bolded and underlined) (SEQ ID NO: 32) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSIIYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI D RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF A DLNFGFKRGRFKVEKQVYQKLEKMLIEKL NYLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFV NQLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGS RLINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAK LTSVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA D ANGAYHIG LKGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 D1255A (SEQ ID NO: 33) (D917, E1006, and A1255 are bolded and underlined) (SEQ ID NO: 33) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSIIYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI D RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF E DLNFGFKRGRFKVEKQVYQKLEKMLIEKLN YLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFVN QLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGSR LINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAKLT SVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA A ANGAYHIGL KGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 D917A/E1006A (SEQ ID NO: 34) (A917, A1006, and D1255 are bolded and underlined) (SEQ ID NO: 34) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSIIYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI A RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF A DLNFGFKRGRFKVEKQVYQKLEKMLIEKL NYLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFV NQLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGS RLINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAK LTSVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA D ANGAYHIG LKGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 D917A/D1255A (SEQ ID NO: 35) (A917, E1006, and A1255 are bolded and underlined) (SEQ ID NO: 35) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSIIYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI A RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF E DLNFGFKRGRFKVEKQVYQKLEKMLIEKLN YLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFVN QLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGSR LINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAKLT SVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA A ANGAYHIGL KGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 E1006A/D1255A (SEQ ID NO: 36) (D917, A1006, and A1255 are bolded and underlined) (SEQ ID NO: 36) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSIIYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI D RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF A DLNFGFKRGRFKVEKQVYQKLEKMLIEKL NYLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFV NQLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGS RLINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAK LTSVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA A ANGAYHIG LKGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN Francisella novicida Cpf1 D917A/E1006A/D1255A (SEQ ID NO: 37) (A917, A1006, and A1255 are bolded and underlined) (SEQ ID NO: 37) MSIYQEFVNKYSLSKTLRFELIPQGKTLENIKARGLILDDEKRAKDYKKAK QIIDKYHQFFIEEILSSVCISEDLLQNYSDVYFKLKKSDDDNLQKDFKSAKDTIKKQISE YIKDSEKFKNLFNQNLIDAKKGQESDLILWLKQSKDNGIELFKANSDITDIDEALEIIK SFKGWTTYFKGFHENRKNVYSSNDIPTSIIYRIVDDNLPKFLENKAKYESLKDKAPEA INYEQIKKDLAEELTFDIDYKTSEVNQRVFSLDEVFEIANFNNYLNQSGITKFNTIIGG KFVNGENTKRKGINEYINLYSQQINDKTLKKYKMSVLFKQILSDTESKSFVIDKLEDD SDVVTTMQSFYEQIAAFKTVEEKSIKETLSLLFDDLKAQKLDLSKIYFKNDKSLTDLS QQVFDDYSVIGTAVLEYITQQIAPKNLDNPSKKEQELIAKKTEKAKYLSLETIKLALE EFNKHRDIDKQCRFEEILANFAAIPMIFDEIAQNKDNLAQISIKYQNQGKKDLLQASA EDDVKAIKDLLDQTNNLLHKLKIFHISQSEDKANILDKDEHFYLVFEECYFELANIVP LYNKIRNYITQKPYSDEKFKLNFENSTLANGWDKNKEPDNTAILFIKDDKYYLGVMN KKNNKIFDDKAIKENKGEGYKKIVYKLLPGANKMLPKVFFSAKSIKFYNPSEDILRIR NHSTHTKNGSPQKGYEKFEFNIEDCRKFIDFYKQSISKHPEWKDFGFRFSDTQRYNSI DEFYREVENQGYKLTFENISESYIDSVVNQGKLYLFQIYNKDFSAYSKGRPNLHTLY WKALFDERNLQDVVYKLNGEAELFYRKQSIPKKITHPAKEAIANKNKDNPKKESVFE YDLIKDKRFTEDKFFFHCPITINFKSSGANKFNDEINLLLKEKANDVHILSI A RGERHL AYYTLVDGKGNIIKQDTFNIIGNDRMKTNYHDKLAAIEKDRDSARKDWKKINNIKE MKEGYLSQVVHEIAKLVIEYNAIVVF A DLNFGFKRGRFKVEKQVYQKLEKMLIEKL NYLVFKDNEFDKTGGVLRAYQLTAPFETFKKMGKQTGIIYYVPAGFTSKICPVTGFV NQLYPKYESVSKSQEFFSKFDKICYNLDKGYFEFSFDYKNFGDKAAKGKWTIASFGS RLINFRNSDKNHNWDTREVYPTKELEKLLKDYSIEYGHGECIKAAICGESDKKFFAK LTSVLNTILQMRNSKTGTELDYLISPVADVNGNFFDSRQAPKNMPQDA A ANGAYHIG LKGLMLLGRIKNNQEGKKLNLVIKNEEYFEFVQNRNN

In some embodiments, the nucleic acid programmable DNA binding protein (napDNAbp) is a nucleic acid programmable DNA binding protein that does not require a canonical (NGG) PAM sequence. In some embodiments, the napDNAbp is an argonaute protein. One example of such a nucleic acid programmable DNA binding protein is an Argonaute protein from Natronobacterium gregoryi (NgAgo). NgAgo is a ssDNA-guided endonuclease. NgAgo binds 5′ phosphorylated ssDNA of ˜24 nucleotides (gDNA) to guide it to its target site and will make DNA double-strand breaks at the gDNA site. In contrast to Cas9, the NgAgo-gDNA system does not require a protospacer-adjacent motif (PAM). Using a nuclease inactive NgAgo (dNgAgo) can greatly expand the bases that may be targeted. The characterization and use of NgAgo have been described in Gao et al., Nat Biotechnol., 2016 July; 34(7):768-73. PubMed PMID: 27136078; Swarts et al., Nature. 507(7491) (2014):258-61; and Swarts et al., Nucleic Acids Res. 43(10) (2015):5120-9, each of which is incorporated herein by reference. The sequence of Natronobacterium gregoryi Argonaute is provided in SEQ ID NO: 38.

Wild type Natronobacteriurn gregoryi Argonaute (SEQ ID NO: 38) (SEQ ID NO: 38) MTVIDLDSTTTADELTSGHTYDISVTLTGVYDNTDEQHPRMSLAFEQD NGERRYITLWKNTTPKDVFTYDYATGSTYIFTNIDYEVKDGYENLTAT YQTTVENATAQEVGTTDEDETFAGGEPLDHHLDDALNETPDDAETESD SGHVMTSFASRDQLPEWTLHTYTLTATDGAKTDTEYARRTLAYTVRQE LYTDHDAAPVATDGLMLLTPEPLGETPLDLDCGVRVEADETRTLDYTT AKDRLLARELVEEGLKRSLWDDYLVRGIDEVLSKEPVLTCDEFDLHER YDLSVEVGHSGRAYLHINFRHRFVPKLTLADIDDDNIYPGLRVKTTYR PRRGHIVWGLRDECATDSLNTLGNQSVVAYHRNNQTPINTDLLDAIEA ADRRVVETRRQGHGDDAVSFPQELLAVEPNTHQIKQFASDGFHQQARS KTRLSASRCSEKAQAFAERLDPVRLNGSTVEFSSEFFTGNNEQQLRLL YENGESVLTFRDGARGAHPDETFSKGIVNPPESFEVAVVLPEQQADTC KAQWDTMADLLNQAGAPPTRSETVQYDAFSSPESISLNVAGAIDPSEV DAAFVVLPPDQEGFADLASPTETYDELKKALANMGIYSQMAYFDRFRD AKIFYTRNVALGLLAAAGGVAFTTEHAMPGDADMFIGIDVSRSYPEDG ASGQINIAATATAVYKDGTILGHSSTRPQLGEKLQSTDVRDIMKNAIL GYQQVTGESPTHIVIHRDGFMNEDLDPATEFLNEQGVEYDIVEIRKQP QTRLLAVSDVQYDTPVKSIAAINQNEPRATVATFGAPEYLATRDGGGL PRPIQIERVAGETDIETLTRQVYLLSQSHIQVHNSTARLPITTAYADQ ASTHATKGYLVQTGAFESNVGFL

In some embodiments, the napDNAbp is a prokaryotic homolog of an Argonaute protein. Prokaryotic homologs of Argonaute proteins are known and have been described, for example, in Makarova K., et al., “Prokaryotic homologs of Argonaute proteins are predicted to function as key components of a novel system of defense against mobile genetic elements”, Biol Direct. 2009 Aug. 25; 4:29. doi: 10.1186/1745-6150-4-29, the entire contents of which is hereby incorporated by reference. In some embodiments, the napDNAbp is a Marinitoga piezophila Argunaute (MpAgo) protein. The CRISPR-associated Marinitoga piezophila Argunaute (MpAgo) protein cleaves single-stranded target sequences using 5′-phosphorylated guides. The 5′ guides are used by all known Argonautes. The crystal structure of an MpAgo-RNA complex shows a guide strand binding site comprising residues that block 5′ phosphate interactions. This data suggests the evolution of an Argonaute subclass with noncanonical specificity for a 5′-hydroxylated guide. See, e.g., Kaya et al., “A bacterial Argonaute with noncanonical guide RNA specificity”, Proc Natl Acad Sci USA. 2016 Apr. 12; 113(15):4057-62, the entire contents of which are hereby incorporated by reference). It should be appreciated that other argonaute proteins may be used, and are within the scope of this disclosure.

In some embodiments, the nucleic acid programmable DNA binding protein (napDNAbp) is a single effector of a microbial CRISPR-Cas system. Single effectors of microbial CRISPR-Cas systems include, without limitation, Cas9, Cpf1, C2c1, C2c2, and C2c3. Typically, microbial CRISPR-Cas systems are divided into Class 1 and Class 2 systems. Class 1 systems have multisubunit effector complexes, while Class 2 systems have a single protein effector. For example, Cas9 and Cpf1 are Class 2 effectors. In addition to Cas9 and Cpf1, three distinct Class 2 CRISPR-Cas systems (C2c1, C2c2, and C2c3) have been described by Shmakov et al., “Discovery and Functional Characterization of Diverse Class 2 CRISPR Cas Systems”, Mol. Cell, 2015 Nov. 5; 60(3): 385-397, the entire contents of which is hereby incorporated by reference. Effectors of two of the systems, C2c1 and C2c3, contain RuvC-like endonuclease domains related to Cpf1. A third system, C2c2 contains an effector with two predicated HEPN RNase domains. Production of mature CRISPR RNA is tracrRNA-independent, unlike production of CRISPR RNA by C2c1. C2c1 depends on both CRISPR RNA and tracrRNA for DNA cleavage. Bacterial C2c2 has been shown to possess a unique RNase activity for CRISPR RNA maturation distinct from its RNA-activated single-stranded RNA degradation activity. These RNase functions are different from each other and from the CRISPR RNA-processing behavior of Cpf1. See, e.g., East-Seletsky, et al., “Two distinct RNase activities of CRISPR-C2c2 enable guide-RNA processing and RNA detection”, Nature, 2016 Oct. 13; 538(7624):270-273, the entire contents of which are hereby incorporated by reference. In vitro biochemical analysis of C2c2 in Leptotrichia shahii has shown that C2c2 is guided by a single CRISPR RNA and can be programed to cleave ssRNA targets carrying complementary protospacers. Catalytic residues in the two conserved HEPN domains mediate cleavage. Mutations in the catalytic residues generate catalytically inactive RNA-binding proteins. See e.g., Abudayyeh et al., “C2c2 is a single-component programmable RNA-guided RNA-targeting CRISPR effector”, Science, 2016 Aug. 5; 353(6299), the entire contents of which are hereby incorporated by reference.

The crystal structure of Alicyclobaccillus acidoterrastris C2c1 (AacC2c1) has been reported in complex with a chimeric single-molecule guide RNA (sgRNA). See e.g., Liu et al., “C2c1-sgRNA Complex Structure Reveals RNA-Guided DNA Cleavage Mechanism”, Mol. Cell, 2017 Jan. 19; 65(2):310-322, the entire contents of which are hereby incorporated by reference. The crystal structure has also been reported in Alicyclobacillus acidoterrestris C2c1 bound to target DNAs as ternary complexes. See e.g., Yang et al., “PAM-dependent Target DNA Recognition and Cleavage by C2C1 CRISPR-Cas endonuclease”, Cell, 2016 Dec. 15; 167(7):1814-1828, the entire contents of which are hereby incorporated by reference. Catalytically competent conformations of AacC2c1, both with target and non-target DNA strands, have been captured independently positioned within a single RuvC catalytic pocket, with C2c1-mediated cleavage resulting in a staggered seven-nucleotide break of target DNA. Structural comparisons between C2c1 ternary complexes and previously identified Cas9 and Cpf1 counterparts demonstrate the diversity of mechanisms used by CRISPR-Cas9 systems.

In some embodiments, the nucleic acid programmable DNA binding protein (napDNAbp) of any of the fusion proteins provided herein may be a C2c1, a C2c2, or a C2c3 protein. In some embodiments, the napDNAbp is a C2c1 protein. In some embodiments, the napDNAbp is a C2c2 protein. In some embodiments, the napDNAbp is a C2c3 protein. In some embodiments, the napDNAbp comprises an amino acid sequence that is at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at ease 99.5% identical to a naturally-occurring C2c1, C2c2, or C2c3 protein. In some embodiments, the napDNAbp is a naturally-occurring C2c1, C2c2, or C2c3 protein. In some embodiments, the napDNAbp comprises an amino acid sequence that is at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at ease 99.5% identical to any one of SEQ ID NOs: 39-40. It should be appreciated that C2c1, C2c2, or C2c3 from other bacterial species may also be used in accordance with the present disclosure.

C2c1 (uniprot.org/uniprot/T0D7A2#) sp|T0D7A2|C2C1_ALIAG CRISPR-associated endonuclease C2c1 OS = Alicyclobacillus acidoterrestris (strain ATCC 49025/DSM 3922/CIP 106132/ NCIMB 13137/GD3B) GN = c2c1 PE = 1 SV = 1 (SEQ ID NO: 39) MAVKSIKVKLRLDDMPEIRAGLWKLHKEVNAGVRYYTEWLSLLRQENLYRRSPNG DGEQECDKTAEECKAELLERLRARQVENGHRGPAGSDDELLQLARQLYELLVPQAI GAKGDAQQIARKFLSPLADKDAVGGLGIAKAGNKPRWVRMREAGEPGWEEEKEKA ETRKSADRTADVLRALADFGLKPLMRVYTDSEMSSVEWKPLRKGQAVRTWDRDM FQQAIERMMSWESWNQRVGQEYAKLVEQKNRFEQKNFVGQEHLVHLVNQLQQDM KEASPGLESKEQTAHYVTGRALRGSDKVFEKWGKLAPDAPFDLYDAEIKNVQRRNT RRFGSHDLFAKLAEPEYQALWREDASFLTRYAVYNSILRKLNHAKMFATFTLPDAT AHPIWTRFDKLGGNLHQYTFLFNEFGERRHAIRFHKLLKVENGVAREVDDVTVPISM SEQLDNLLPRDPNEPIALYFRDYGAEQHFTGEFGGAKIQCRRDQLAHMHRRRGARD VYLNVSVRVQSQSEARGERRPPYAAVFRLVGDNHRAFVHFDKLSDYLAEHPDDGKL GSEGLLSGLRVMSVDLGLRTSASISVFRVARKDELKPNSKGRVPFFFPIKGNDNLVAV HERSQLLKLPGETESKDLRAIREERQRTLRQLRTQLAYLRLLVRCGSEDVGRRERSW AKLIEQPVDAANHMTPDWREAFENELQKLKSLHGICSDKEWMDAVYESVRRVWRH MGKQVRDWRKDVRSGERPKIRGYAKDVVGGNSIEQIEYLERQYKFLKSWSFFGKVS GQVIRAEKGSRFAITLREHIDHAKEDRLKKLADRIIMEALGYVYALDERGKGKWVA KYPPCQLILLEELSEYQFNNDRPPSENNQLMQWSHRGVFQELINQAQVHDLLVGTM YAAFSSRFDARTGAPGIRCRRVPARCTQEHNPEPFPWWLNKFVVEHTLDACPLRAD DLIPTGEGEIFVSPFSAEEGDFHQIHADLNAAQNLQQRLWSDFDISQIRLRCDWGEVD GELVLIPRLTGKRTADSYSNKVFYTNTGVTYYERERGKKRRKVFAQEKLSEEEAELL VEADEAREKSVVLMRDPSGIINRGNWTRQKEFWSMVNQRIEGYLVKQIRSRVPLQD SACENTGDI C2c2 (uniprot.org/uniprot/P0DOC6) >sp|P0DOC6|C2C2_LEPSD CRISPR-associated endoribonuclease C2c2 OS = Leptotrichia shahii (strain DSM 19757/CCUG 47503/OP 107916/JCM 16776/ LB37) GN = c2c2 PE = 1 S V = 1 (SEQ ID NO: 40) MGNLFGHKRWYEVRDKKDFKIKRKVKVKRNYDGNKYILNINENNNKEKIDNNKFIR KYINYKKNDNILKEFTRKFHAGNILFKLKGKEGIIRIENNDDFLETEEVVLYIEAYGKS EKLKALGITKKKIIDEAIRQGITKDDKKIEIKRQENEEEIEIDIRDEYTNKTLNDCSIILRI IENDELETKKSIYEIFKNINMSLYKIIEKIIENETEKVFENRYYEEHLREKLLKDDKIDVI LTNFMEIREKIKSNLEILGFVKFYLNVGGDKKKSKNKKMLVEKILNINVDLTVEDIAD FVIKELEFWNITKRIEKVKKVNNEFLEKRRNRTYIKSYVLLDKHEKFKIERENKKDKI VKFFVENIKNNSIKEKIEKILAEFKIDELIKKLEKELKKGNCDTEIFGIFKKHYKVNFDS KKFSKKSDEEKELYKIIYRYLKGRIEKILVNEQKVRLKKMEKIEIEKILNESILSEKILK RVKQYTLEHIMYLGKLRHNDIDMTTVNTDDFSRLHAKEELDLELITFFASTNMELNK IFSRENINNDENIDFFGGDREKNYVLDKKILNSKIKIIRDLDFIDNKNNITNNFIRKFTKI GTNERNRILHAISKERDLQGTQDDYNKVINIIQNLKISDEEVSKALNLDVVFKDKKNII TKINDIKISEENNNDIKYLPSFSKVLPEILNLYRNNPKNEPFDTIETEKIVLNALIYVNKE LYKKLILEDDLEENESKNIFLQELKKTLGNIDEIDENIIENYYKNAQISASKGNNKAIK KYQKKVIECYIGYLRKNYEELFDFSDFKMNIQEIKKQIKDINDNKTYERITVKTSDKTI VINDDFEYIISIFALLNSNAVINKIRNRFFATSVWLNTSEYQNIIDILDEIMQLNTLRNEC ITENWNLNLEEFIQKMKEIEKDFDDFKIQTKKEIFNNYYEDIKNNILTEFKDDINGCDV LEKKLEKIVIFDDETKFEIDKKSNILQDEQRKLSNINKKDLKKKVDQYIKDKDQEIKS KILCRIIFNSDFLKKYKKEIDNLIEDMESENENKFQEIYYPKERKNELYIYKKNLFLNIG NPNFDKIYGLISNDIKMADAKFLFNIDGKNIRKNKISEIDAILKNLNDKLNGYSKEYKE KYIKKLKENDDFFAKNIQNKNYKSFEKDYNRVSEYKKIRDLVEFNYLNKIESYLIDIN WKLAIQMARFERDMHYIVNGLRELGIIKLSGYNTGISRAYPKRNGSDGFYTTTAYYK FFDEESYKKFEKICYGFGIDLSENSEINKPENESIRNYISHFYIVRNPFADYSIAEQIDRV SNLLSYSTRYNNSTYASVFEVFKKDVNLDYDELKKKFKLIGNNDILERLMKPKKVSV LELESYNSDYIKNLIIELLTKIENTNDTL Cas9 Domains of Nucleobase Editors

In some aspects, a nucleic acid programmable DNA binding protein (napDNAbp) is a Cas9 domain. Non-limiting, exemplary Cas9 domains are provided herein. The Cas9 domain may be a nuclease active Cas9 domain, a nuclease inactive Cas9 domain, or a Cas9 nickase. In some embodiments, the Cas9 domain is a nuclease active domain. For example, the Cas9 domain may be a Cas9 domain that cuts both strands of a duplexed nucleic acid (e.g., both strands of a duplexed DNA molecule). In some embodiments, the Cas9 domain comprises any one of the amino acid sequences as set forth in SEQ ID NOs: 4-29. In some embodiments the Cas9 domain comprises an amino acid sequence that is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to any Cas9 provided herein, or to one of the amino acid sequences set forth in SEQ ID NOs: 4-29. In some embodiments, the Cas9 domain comprises an amino acid sequence that has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50 or more mutations compared to any Cas9 provided herein, or to any one of the amino acid sequences set forth in SEQ ID NOs: 4-29. In some embodiments, the Cas9 domain comprises an amino acid sequence that has at least 10, at least 15, at least 20, at least 30, at least 40, at least 50, at least 60, at least 70, at least 80, at least 90, at least 100, at least 150, at least 200, at least 250, at least 300, at least 350, at least 400, at least 500, at least 600, at least 700, at least 800, at least 900, at least 1000, at least 1100, or at least 1200 identical contiguous amino acid residues as compared to any Cas9 provided herein or any one of the amino acid sequences set forth in SEQ ID NOs: 4-29.

In some embodiments, the Cas9 domain is a nuclease-inactive Cas9 domain (dCas9). For example, the dCas9 domain may bind to a duplexed nucleic acid molecule (e.g., via a gRNA molecule) without cleaving either strand of the duplexed nucleic acid molecule. In some embodiments, the nuclease-inactive dCas9 domain comprises a D10X mutation and a H840X mutation of the amino acid sequence set forth in SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as one of the amino acid sequences provided in SEQ ID NOs: 4-26, wherein X is any amino acid change. In some embodiments, the nuclease-inactive dCas9 domain comprises a D10A mutation and a H840A mutation of the amino acid sequence set forth in SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any one of the amino acid sequences provided in SEQ ID NOs: 4-26. As one example, a nuclease-inactive Cas9 domain comprises the amino acid sequence set forth in SEQ ID NO: 9 (Cloning vector pPlatTET-gRNA2, Accession No. BAV54124).

MDKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIG ALLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFF HRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTD KADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLF EENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALS LGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAK NLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQL PEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVK LNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIE KILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQS FIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAF LSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFN ASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLK TYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSD GFANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKK GILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRI EEGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRL SDYDVDAIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNY WRQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHV AQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINN YHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEI GKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGR DFATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWD PKKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEK NPIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNE LALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQIS EFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAA FKYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD (SEQ ID NO: 9; see, e.g., Qi et al., ″Repurposing CRISPR as an RNA-guided platform for sequence- specific control of gene expression.″ Cell. 2013; 152(5):1173-83, the entire contents of which are incorporated herein by reference).

Additional suitable nuclease-inactive dCas9 domains will be apparent to those of skill in the art based on this disclosure and knowledge in the field, and are within the scope of this disclosure. Such additional exemplary suitable nuclease-inactive Cas9 domains include, but are not limited to, D10A/H840A, D10A/D839A/H840A, and D10A/D839A/H840A/N863A mutant domains (See, e.g., Prashant et al., CAS9 transcriptional activators for target specificity screening and paired nickases for cooperative genome engineering. Nature Biotechnology. 2013; 31(9): 833-838, the entire contents of which are incorporated herein by reference). In some embodiments the dCas9 domain comprises an amino acid sequence that is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to any one of the dCas9 domains provided herein. In some embodiments, the Cas9 domain comprises an amino acid sequences that has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more mutations compared to any one of the amino acid sequences set forth in SEQ ID NOs: 7, 8, 9, or 22. In some embodiments, the Cas9 domain comprises an amino acid sequence that has at least 10, at least 15, at least 20, at least 30, at least 40, at least 50, at least 60, at least 70, at least 80, at least 90, at least 100, at least 150, at least 200, at least 250, at least 300, at least 350, at least 400, at least 500, at least 600, at least 700, at least 800, at least 900, at least 1000, at least 1100, or at least 1200 identical contiguous amino acid residues as compared to any one of the amino acid sequences set forth in SEQ ID NOs: 7, 8, 9, or 22.

In some embodiments, the Cas9 domain is a Cas9 nickase. The Cas9 nickase may be a Cas9 protein that is capable of cleaving only one strand of a duplexed nucleic acid molecule (e.g., a duplexed DNA molecule). In some embodiments the Cas9 nickase cleaves the target strand of a duplexed nucleic acid molecule, meaning that the Cas9 nickase cleaves the strand that is base paired to (complementary to) a gRNA (e.g., an sgRNA) that is bound to the Cas9. In some embodiments, a Cas9 nickase comprises a D10A mutation and has a histidine at position 840 of SEQ ID NO: 6, or a mutation in any Cas9 provided herein, such as any one of SEQ ID NOs: 4-26. For example, a Cas9 nickase may comprise the amino acid sequence as set forth in SEQ ID NO: 10, 13, 16, or 21. In some embodiments, the Cas9 nickase cleaves the non-target, non-base-edited strand of a duplexed nucleic acid molecule, meaning that the Cas9 nickase cleaves the strand that is not base paired to a gRNA (e.g., an sgRNA) that is bound to the Cas9. In some embodiments, a Cas9 nickase comprises an H840A mutation and has an aspartic acid residue at position 10 of SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any one of SEQ ID NOs: 4-26. In some embodiments the Cas9 nickase comprises an amino acid sequence that is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to any one of the Cas9 nickases provided herein. Additional suitable Cas9 nickases will be apparent to those of skill in the art based on this disclosure and knowledge in the field, and are within the scope of this disclosure.

Cas9 Domains with Reduced PAM Exclusivity

Some aspects of the disclosure provide Cas9 domains that have different PAM specificities. Typically, Cas9 proteins, such as Cas9 from S. pyogenes (spCas9), require a canonical NGG PAM sequence to bind a particular nucleic acid region, where the “N” in “NGG” is adenine (A), thymine (T), guanine (G), or cytosine (C), and the G is guanine. This may limit the ability to edit desired bases within a genome. In some embodiments, the base editing fusion proteins provided herein need to be positioned at a precise location, for example, where a target base is within a 4 base region (e.g., a “deamination window”), which is approximately 15 bases upstream of the PAM. See Komor, A. C., et al., “Programmable editing of a target base in genomic DNA without double-stranded DNA cleavage” Nature 533, 420-424 (2016), the entire contents of which are hereby incorporated by reference. In some embodiments, the deamination window is within a 2, 3, 4, 5, 6, 7, 8, 9, or 10 base region. In some embodiments, the deamination window is 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 bases upstream of the PAM. Accordingly, in some embodiments, any of the fusion proteins provided herein may contain a Cas9 domain that is capable of binding a nucleotide sequence that does not contain a canonical (e.g., NGG) PAM sequence. Cas9 domains that bind to non-canonical PAM sequences have been described in the art and would be apparent to the skilled artisan. For example, Cas9 domains that bind non-canonical PAM sequences have been described in Kleinstiver, B. P., et al., “Engineered CRISPR-Cas9 nucleases with altered PAM specificities” Nature 523, 481-485 (2015); and Kleinstiver, B. P., et al., “Broadening the targeting range of Staphylococcus aureus CRISPR-Cas9 by modifying PAM recognition” Nature Biotechnology 33, 1293-1298 (2015); the entire contents of each are hereby incorporated by reference.

In some embodiments, the Cas9 domain is a Cas9 domain from Staphylococcus aureus (SaCas9). In some embodiments, the SaCas9 domain is a nuclease active SaCas9, a nuclease inactive SaCas9 (SaCas9d), or a SaCas9 nickase (SaCas9n). In some embodiments, the SaCas9 comprises the amino acid sequence SEQ ID NO: 12. In some embodiments, the SaCas9 comprises a N579X mutation of SEQ ID NO: 12, or a corresponding mutation in any of the amino acid sequences provided in SEQ ID NOs: 13-14, wherein X is any amino acid except for N. In some embodiments, the SaCas9 comprises a N579A mutation of SEQ ID NO: 12, or a corresponding mutation in any of the amino acid sequences provided in SEQ ID NOs: 13-14.

In some embodiments, the SaCas9 domain, the SaCas9d domain, or the SaCas9n domain can bind to a nucleic acid sequence having a non-canonical PAM. In some embodiments, the SaCas9 domain, the SaCas9d domain, or the SaCas9n domain can bind to a nucleic acid sequence having a NNGRRT PAM sequence, where N=A, T, C, or G, and R=A or G. In some embodiments, the SaCas9 domain comprises one or more of E781X, N967X, and R1014X mutation of SEQ ID NO: 12, or a corresponding mutation in any of the amino acid sequences provided in SEQ ID NOs: 13-14, wherein X is any amino acid. In some embodiments, the SaCas9 domain comprises one or more of a E781K, a N967K, and a R1014H mutation of SEQ ID NO: 12, or one or more corresponding mutation in any of the amino acid sequences provided in SEQ ID NOs: 13-14. In some embodiments, the SaCas9 domain comprises a E781K, a N967K, or a R1014H mutation of SEQ ID NO: 12, or corresponding mutations in any of the amino acid sequences provided in SEQ ID NOs: 13-14.

In some embodiments, the Cas9 domain of any of the fusion proteins provided herein comprises an amino acid sequence that is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to any one of SEQ ID NOs: 12-14. In some embodiments, the Cas9 domain of any of the fusion proteins provided herein comprises the amino acid sequence of any one of SEQ ID NOs: 12-14. In some embodiments, the Cas9 domain of any of the fusion proteins provided herein consists of the amino acid sequence of any one of SEQ ID NOs: 12-14.

Exemplary SaCas9 sequence (SEQ ID NO: 12) KRNYILGLDIGITSVGYGIIDYETRDVIDAGVRLFKEANVENNEGRRSK RGARRLKRRRRHRIQRVKKLLFDYNLLTDHSELSGINTPYEARVKGLSQ KLSEEEFSAALLHLAKRRGVHNVNEVEEDTGNELSTKEQISRNSKALEE KYVAELQLERLKKDGEVRGSINRFKTSDYVKEAKQLLKVQKAYHQLDQS FIDTYIDLLETRRTYYEGPGEGSPFGWKDIKEWYEMLMGHCTYFPEELR SVKYAYNADLYNALNDLNNLVITRDENEKLEYYEKFQIIENVFKQKKKP TLKQIAKEILVNEEDIKGYRVTSTGKPEFTNLKVYHDIKDITARKEIIE NAELLDQIAKILTIYQSSEDIQEELTNLNSELTQEEIEQISNLKGYTGT HNLSLKAINLILDELWHTNDNQIAIFNRLKLVPKKVDLSQQKEIPTTLV DDFILSPVVKRSFIQSIKVINAIIKKYGLPNDIIIELAREKNSKDAQKM INEMQKRNRQTNERIEEIIRTTGKENAKYLIEKIKLHDMQEGKCLYSLE AIPLEDLLNNPFNYEVDHIIPRSVSFDNSFNNKVLVKQEE N SKKGNRTP FQYLSSSDSKISYETFKKHILNLAKGKGRISKTKKEYLLEERDINRFSV QKDFINRNLVDTRYATRGLMNLLRSYFRVNNLDVKVKSINGGFTSFLRR KWKFKKERNKGYKHHAEDALIIANADFIFKEWKKLDKAKKVMENQMFEE KQAESMPEIETEQEYKEIFITPHQIKHIKDFKDYKYSHRVDKKPNRELI NDTLYSTRKDDKGNTLIVNNLNGLYDKDNDKLKKLINKSPEKLLMYHHD PQTYQKLKLIMEQYGDEKNPLYKYYEETGNYLTKYSKKDNGPVIKKIKY YGNKLNAHLDITDDYPNSRNKVVKLSLKPYRFDVYLDNGVYKFVTVKNL DVIKKENYYEVNSKCYEEAKKLKKISNQAEFIASFYNNDLIKINGELYR VIGVNNDLLNRIEVNMIDITYREYLENMNDKRPPRIIKTIASKTQSIKK YSTDILGNLYEVKSKKHPQIIKKG

Residue N579 of SEQ ID NO: 12, which is underlined and in bold, may be mutated (e.g., to a A579) to yield a SaCas9 nickase.

Exemplary SaCas9n sequence (SEQ ID NO: 13) KRNYILGLDIGITSVGYGIIDYETRDVIDAGVRLFKEANVENNEGRRS KRGARRLKRRRRHRIQRVKKLLFDYNLLTDHSELSGINIPYEARVKGL SQKLSEEEFSAALLHLAKRRGVHNVNEVEEDTGNELSTKEQISRNSKA LEEKYVAELQLERLKKDGEVRGSINRFKTSDYVKEAKQLLKVQKAYHQ LDQSFIDTYIDLLETRRTYYEGPGEGSPFGWKDIKEWYEMLMGHCTYF PEELRSVKYAYNADLYNALNDLNNLVITRDENEKLEYYEKFQIIENVF KQKKKPTLKQIAKEILVNEEDIKGYRVTSTGKPEFTNLKVYHDIKDIT ARKEIIENAELLDQIAKILTIYQSSEDIQEELTNLNSELTQEEIEQIS NLKGYTGTHNLSLKAINLILDELWHTNDNQIAIFNRLKLVPKKVDLSQ QKEIPTTLVDDFILSPVVKRSFIQSIKVINAIIKKYGLPNDIIIELAR EKNSKDAQKMINEMQKRNRQTNERIEEIIRTTGKENAKYLIEKIKLHD MQEGKCLYSLEAIPLEDLLNNPFNYEVDHIIPRSVSFDNSFNNKVLVK QEE A SKKGNRTPFQYLSSSDSKISYETFKKHILNLAKGKGRISKTKKE YLLEERDINIRFSVQKDFINRNLVDTRYATRGLMNLLRSYFRVNNLDV KVKSINGGFTSFLRRKWKFKKERNKGYKHHAEDALIIANADFIFKEWK KLDKAKKVMENQMFEEKQAESMPEIETEQEYKEIFITPHQIKHIKDFK DYKYSHRVDKKPNRELINDTLYSTRKDDKGNTLIVNNLNGLYDKDNDK LKKLINKSPEKLLMYHHDPQTYQKLKLIMEQYGDEKNPLYKYYEETGN YLTKYSKKDNGPVIKKIKYYGNKLNAHLDITDDYPNSRNKVVKLSLKP YRFDVYLDNGVYKFVTVKNLDVIKKENYYEVNSKCYEEAKKLKKISNQ AEFIASFYNNDLIKINGELYRVIGVNNDLLNRIEVNMIDITYREYLEN MNDKRPPRIIKTIASKTQSIKKYSTDILGNLYEVKSKKHPQIIKKG.

Residue A579 of SEQ ID NO: 13, which can be mutated from N579 of SEQ ID NO: 12 to yield a SaCas9 nickase, is underlined and in bold.

Exemplary SaKKH Cas9 (SEQ ID NO: 14) KRNYILGLDIGITSVGYGIIDYETRDVIDAGVRLFKEANVENNEGRR SKRGARRLKRRRRHRIQRVKKLLFDYNLLTDHSELSGINPYEARVKG LSQKLSEEEFSAALLHLAKRRGVHNVNEVEEDTGNELSTKEQISRNS KALEEKYVAELQLERLKKDGEVRGSINRFKTSDYVKEAKQLLKVQKA YHQLDQSFIDTYIDLLETRRTYYEGPGEGSPFGWKDIKEWYEMLMGH CTYFPEELRSVKYAYNADLYNALNDLNNLVITRDENEKLEYYEKFQI IENVFKQKKKPTLKQIAKEILVNEEDIKGYRVTSTGKPEFTNLKVYH DIKDITARKEIIENAELLDQIAKILTIYQSSEDIQEELTNLNSELTQ EEIEQISNLKGYTGTHNLSLKAINLILDELWHTNDNQIAIFNRLKLV PKKVDLSQQKEIPTTLVDDFILSPVVKRSFIQSIKVINAIIKKYGLP NDIIIELAREKNSKDAQKMINEMQKRNRQTNERIEEIIRTTGKENAK YLIEKIKLHDMQEGKCLYSLEAIPLEDLLNNPFNYEVDHIIPRSVSF DNSFNNKVLVKQEE A SKKGNRTPFQYLSSSDSKISYETFKKHILNLA KGKGRISKTKKEYLLEERDINIRFSVQKDFINRNLVDTRYATRGLMN LLRSYFRVNNLDVKVKSINGGFTSFLRRKWKFKKERNKGYKHHAEDA LIIANADFIFKEWKKLDKAKKVMENQMFEEKQAESMPEIETEQEYKE IFITPHQIKHIKDFKDYKYSHRVDKKPNR K LINDTLYSTRKDDKGNT LIVNNLNGLYDKDNDKLKKLINKSPEKLLMYHHDPQTYQKLKLIMEQ YGDEKNPLYKYYEETGNYLTKYSKKDNGPVIKKIKYYGNKLNAHLDI TDDYPNSRNKVVKLSLKPYRFDVYLDNGVYKFVTVKNLDVIKKENYY EVNSKCYEEAKKLKKISNQAEFIASFY K NDLIKINGELYRVIGVNND LLNRIEVNMIDITYREYLENMNDKRPP H IIKTIASKTQSIKKYSTDI LGNLYEVKSKKHPQIIKKG.

Residue A579 of SEQ ID NO: 14, which can be mutated from N579 of SEQ ID NO: 12 to yield a SaCas9 nickase, is underlined and in bold. Residues K781, K967, and H1014 of SEQ ID NO: 14, which can be mutated from E781, N967, and R1014 of SEQ ID NO: 12 to yield a SaKKH Cas9 are underlined and in italics.

In some embodiments, the Cas9 domain is a Cas9 domain from Streptococcus pyogenes (SpCas9). In some embodiments, the SpCas9 domain is a nuclease active SpCas9, a nuclease inactive SpCas9 (SpCas9d), or a SpCas9 nickase (SpCas9n). In some embodiments, the SpCas9 comprises the amino acid sequence SEQ ID NO: 15. In some embodiments, the SpCas9 comprises a D9X mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, wherein X is any amino acid except for D. In some embodiments, the SpCas9 comprises a D9A mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the SpCas9 domain, the SpCas9d domain, or the SpCas9n domain can bind to a nucleic acid sequence having a non-canonical PAM. In some embodiments, the SpCas9 domain, the SpCas9d domain, or the SpCas9n domain can bind to a nucleic acid sequence having a NGG, a NGA, or a NGCG PAM sequence. In some embodiments, the SpCas9 domain comprises one or more of a D1134X, a R1334X, and a T1336X mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, wherein X is any amino acid. In some embodiments, the SpCas9 domain comprises one or more of a D1134E, R1334Q, and T1336R mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the SpCas9 domain comprises a D1134E, a R1334Q, and a T1336R mutation of SEQ ID NO: 15, or corresponding mutations in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the SpCas9 domain comprises one or more of a D1134X, a R1334X, and a T1336X mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, wherein X is any amino acid. In some embodiments, the SpCas9 domain comprises one or more of a D1134V, a R1334Q, and a T1336R mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the SpCas9 domain comprises a D1134V, a R1334Q, and a T1336R mutation of SEQ ID NO: 15, or corresponding mutations in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the SpCas9 domain comprises one or more of a D1134X, a G1217X, a R1334X, and a T1336X mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herein, such as any one of the amino acid sequences provided in SEQ ID NOs: 4-26, wherein X is any amino acid. In some embodiments, the SpCas9 domain comprises one or more of a D1134V, a G1217R, a R1334Q, and a T1336R mutation of SEQ ID NO: 15, or a corresponding mutation in any Cas9 provided herin, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the SpCas9 domain comprises a D1134V, a G1217R, a R1334Q, and a T1336R mutation of SEQ ID NO: 15, or corresponding mutations in any Cas9 provided herein, such as any one of the amino acid sequences provided in SEQ ID NOs: 4-26.

In some embodiments, the Cas9 domain of any of the fusion proteins provided herein comprises an amino acid sequence that is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to any one of SEQ ID NOs: 15-19. In some embodiments, the Cas9 domain of any of the fusion proteins provided herein comprises the amino acid sequence of any one of SEQ ID NOs: 15-19. In some embodiments, the Cas9 domain of any of the fusion proteins provided herein consists of the amino acid sequence of any one of SEQ ID NOs: 15-19.

Exemplary SpCas9 (SEQ ID NO: 15) DKKYSIGLDIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGALL FDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLEESFLVEED KKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRLIYLALAHMIKFRGH FLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINASGVDAKAILSARLSKSRRLENLI AQLPGEKKNGLFGNLIALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIG DQYADLFLAAKNLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQ QLPEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLL RKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARG NSRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPKHSLLY EYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKK IECFDSVETSGVEDRFNASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREM IEERLKTYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDGF ANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKGILQTVKVVD ELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVE NTQLQNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKVLT RSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDK AGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQ FYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQ EIGKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRDFATVRK VLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVAYS VLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLPK YSLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYEKLKGSPEDNEQKQ LFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLT NLGAPAAFKYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD Exemplary SpCas9n (SEQ ID NO: 16) DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGALL FDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLEESFLVEED KKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRLIYLALAHMIKFRGH FLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINASGVDAKAILSARLSKSRRLENLI AQLPGEKKNGLFGNLIALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIG DQYADLFLAAKNLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQ QLPEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLL RKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARG NSRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPKHSLLY EYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKK IECFDSVETSGVEDRFNASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREM IEERLKTYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDGF ANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKGILQTVKVVD ELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVE NTQLQNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKVLT RSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDK AGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQ FYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQ EIGKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRDFATVRK VLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVAYS VLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLPK YSLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYEKLKGSPEDNEQKQ LFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLT NLGAPAAFKYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD Exemplary SpEQR Cas9 (SEQ ID NO: 17) DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGALL FDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLEESFLVEED KKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRLIYLALAHMIKFRGH FLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINASGVDAKAILSARLSKSRRLENLI AQLPGEKKNGLFGNLIALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIG DQYADLFLAAKNLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQ QLPEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLL RKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARG NSRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPKHSLLY EYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKK IECFDSVETSGVEDRFNASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREM IEERLKTYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDGF ANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKGILQTVKVVD ELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVE NTQLQNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKVLT RSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDK AGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQ FYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQ EIGKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRDFATVRK VLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDPKKYGGF E SPTVAYS VLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLPK YSLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYEKLKGSPEDNEQKQ LFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLT NLGAPAAFKYFDTTIDRK Q Y R STKEVLDATLIHQSITGLYETRIDLSQLGGD

Residues E1134, Q1334, and R1336 of SEQ ID NO: 17, which can be mutated from D1134, R1334, and T1336 of SEQ ID NO: 15 to yield a SpEQR Cas9, are underlined and in bold.

Exemplary SpVQR Cas9 (SEQ ID NO: 18) DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGA LLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFH RLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDK ADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFE ENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSL GLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKN LSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLP EKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKL NREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEK ILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSF IERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFNA SLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKT YAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDG FANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKG ILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIE EGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLS DYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYW RQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVA QILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNY HHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIG KATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRD FATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDP KKYGGF V SPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKN PIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNEL ALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAF KYFDTTIDRK Q Y R STKEVLDATLIHQSITGLYETRIDLSQLGGD

Residues V1134, Q1334, and R1336 of SEQ ID NO: 18, which can be mutated from D1134, R1334, and T1336 of SEQ ID NO: 15 to yield a SpVQR Cas9, are underlined and in bold.

Exemplary SpVRER Cas9 (SEQ ID NO: 19) DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIG ALLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSF FHRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDS TDKADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYN QLFEENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNL IALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADL FLAAKNLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKA LVRQQLPEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDG TEELLVKLNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFL KDNREKIEKILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEV VDKGASAQSFIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKY VTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDS VEISGVEDRFNASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTL FEDREMIEERLKTYAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDK QSGKTILDFLKSDGFANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLH EHIANLAGSPAIKKGILQTVKVVDELVKVMGRHKPENIVIEMARENQT TQKGQKNSRERMKRIEEGIKELGSQILKEHPVENTQLQNEKLYLYYLQ NGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKVLTRSDKNRG KSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDK AGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKSK LVSDFRKDFQFYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFV YGDYKVYDVRKMIAKSEQEIGKATAKYFFYSNIMNFFKTEITLANGEI RKRPLIETNGETGEIVWDKGRDFATVRKVLSMPQVNIVKKTEVQTGGF SKESILPKRNSDKLIARKKDWDPKKYGGF V SPTVAYSVLVVAKVEKGK SKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLPKY SLFELENGRKRMLASA R ELQKGNELALPSKYVNFLYLASHYEKLKGSP EDNEQKQLFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKH RDKPIREQAENIIHLFTLTNLGAPAAFKYFDTTIDRK E Y R STKEVLDA TLIHQSITGLYETRIDLSQLGGD

Residues V1134, R1217, Q1334, and R1336 of SEQ ID NO: 19, which can be mutated from D1134, G1217, R1334, and T1336 of SEQ ID NO: 15 to yield a SpVRER Cas9, are underlined and in bold.

High Fidelity Cas9 Domains

Some aspects of the disclosure provide high fidelity Cas9 domains of the nucleobase editors provided herein. In some embodiments, high fidelity Cas9 domains are engineered Cas9 domains comprising one or more mutations that decrease electrostatic interactions between the Cas9 domain and the sugar-phosphate backbone of DNA, as compared to a corresponding wild-type Cas9 domain. Without wishing to be bound by any particular theory, high fidelity Cas9 domains that have decreased electrostatic interactions with the sugar-phosphate backbone of DNA may have less off-target effects. In some embodiments, the Cas9 domain (e.g., a wild type Cas9 domain) comprises one or more mutations that decrease the association between the Cas9 domain and the sugar-phosphate backbone of DNA. In some embodiments, a Cas9 domain comprises one or more mutations that decreases the association between the Cas9 domain and the sugar-phosphate backbone of DNA by at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, or more.

In some embodiments, any of the Cas9 fusion proteins provided herein comprise one or more of N497X, R661X, Q695X, and/or Q926X mutation of the amino acid sequence provided in SEQ ID NO: 6, or corresponding mutation(s) in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, wherein X is any amino acid. In some embodiments, any of the Cas9 fusion proteins provided herein comprise one or more of N497A, R661A, Q695A, and/or Q926A mutation of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the Cas9 domain comprises a D10A mutation of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26. In some embodiments, the Cas9 domain (e.g., of any of the fusion proteins provided herein) comprises the amino acid sequence as set forth in SEQ ID NO: 20. In some embodiments, the Cas9 domain comprises an amino acid sequence that is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to SEQ ID NO: 20. Cas9 domains with high fidelity are known in the art and would be apparent to the skilled artisan. For example, Cas9 domains with high fidelity have been described in Kleinstiver, B. P., et al. “High-fidelity CRISPR-Cas9 nucleases with no detectable genome-wide off-target effects.” Nature 529, 490-495 (2016); and Slaymaker, I. M., et al. “Rationally engineered Cas9 nucleases with improved specificity.” Science 351, 84-88 (2015); the entire contents of each are incorporated herein by reference.

It should be appreciated that any of the base editors provided herein, for example, any of the C to G base editors provided herein, may be converted into high fidelity base editors by modifying the Cas9 domain as described herein to generate high fidelity base editors, for example, a high fidelity C to G base editor. In some embodiments, the high fidelity Cas9 domain is a dCas9 domain. In some embodiments, the high fidelity Cas9 domain is a nCas9 domain.

High Fidelity Cas9 domain where mutations relative to Cas9 of SEQ ID NO: 6 are shown in bold and underlines

(SEQ ID NO: 20) DKKYSIGL A IGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIG ALLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSF FHRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDS TDKADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYN QLFEENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNL IALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADL FLAAKNLSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKA LVRQQLPEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDG TEELLVKLNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFL KDNREKIEKILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEV VDKGASAQSFIERMT A FDKNLPNEKVLPKHSLLYEYFTVYNELTKVKY VTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDS VEISGVEDRFNASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTL FEDREMIEERLKTYAHLFDDKVMKQLKRRRYTGWG A LSRKLINGIRDK QSGKTILDFLKSDGFANRNFM A LIHDDSLTFKEDIQKAQVSGQGDSLH EHIANLAGSPAIKKGILQTVKVVDELVKVMGRHKPENIVIEMARENQT TQKGQKNSRERMKRIEEGIKELGSQILKEHPVENTQLQNEKLYLYYLQ NGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKVLTRSDKNRG KSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDK AGFIKRQLVETR A ITKHVAQILDSRMNTKYDENDKLIREVKVITLKSK LVSDFRKDFQFYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFV YGDYKVYDVRKMIAKSEQEIGKATAKYFFYSNIMNFFKTEITLANGEI RKRPLIETNGETGEIVWDKGRDFATVRKVLSMPQVNIVKKTEVQTGGF SKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVAYSVLVVAKVEKGK SKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLPKY SLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYEKLKGSP EDNEQKQLFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKH RDKPIREQAENIIHLFTLTNLGAPAAFKYFDTTIDRKRYTSTKEVLDA TLIHQSITGLYETRIDLSQLGGD

The disclosure also provides fragments of napDNAbps, such as truncations of any of the napDNAbps provided herein. In some embodiments, the napDNAbp is an N-terminal truncation, where one or more amino acids are absent from the N-terminus of the napDNAbp. In some embodiments, the napDNAbp is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the N-terminus of the napDNAbp. For example, the N-terminal truncation of the napDNAbp may be an N-terminal truncation of any napDNAbp provided herein, such as any one of the napDNAbps provided in any one of SEQ ID NOs: 4-40. In some embodiments, the napDNAbp is a C-terminal truncation, where one or more amino acids are absent from the C-terminus of the napDNAbp. In some embodiments, the napDNAbp is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the C-terminus of the napDNAbp. For example, the C-terminal truncation of the napDNAbp may be a C-terminal truncation of any napDNAbp provided herein, such as any one of the NAPs provided in any one of SEQ ID NOs: 4-40.

In some embodiments, any of the napDNAbps provided herein have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to any napDNAbp provided herein, such as any one of the napDNAbps provided in SEQ ID NOs: 4-40.

Uracil Binding Proteins (UBP)

A uracil binding protein, or UBP, refers to a protein that is capable of binding to uracil. In some embodiments, the uracil binding protein is a uracil modifying enzyme. In some embodiments, the uracil binding protein is a uracil base excision enzyme. In some embodiments, the uracil binding protein is a uracil DNA glycosylase (UDG). In some embodiments, a uracil binding protein binds uracil with an affinity that is at least 1%, 2%, 3%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or at least 95% of the affinity that a wild type UDG (e.g., a human UDG) binds to uracil. In some embodiments, the uracil binding protein may have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to wild type uracil binding protein such as a wild type UDG (e.g., a human UDG) binds to uracil.

In some embodiments, the UBP is a uracil modifying enzyme. In some embodiments, the UBP is a uracil base excision enzyme. In some embodiments, the UBP is a uracil DNA glycosylase. In some embodiments, the UBP is any of the uracil binding proteins provided herein. For example, the UBP may be a UDG, a UdgX, a UdgX*, a UdgX_On, or a SMUG1. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a uracil binding protein, a uracil base excision enzyme or a uracil DNA glycosylase (UDG) enzyme. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the uracil binding proteins provided herein, for example, any of the UBP and UBP variants provided below. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 48-53. In some embodiments, the UBP comprises the amino acid sequence of any one of SEQ ID NOs: 48-53. In some embodiments, the uracil binding protein has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to any UBP provided herein, such as any one of SEQ ID NOs: 48-53.

The disclosure also provides fragments of UBPs, such as truncations of any of the UBPs provided herein. In some embodiments, the UBP is an N-terminal truncation, where one or more amino acids are absent from the N-terminus of the UBP. In some embodiments, the UBP is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the N-terminus of the UBP. For example, the N-terminal truncation of the UBP may be an N-terminal truncation of any UBP provided herein, such as any one of the UBPs provided in any one of SEQ ID NOs: 48-53. In some embodiments, the UBP is a C-terminal truncation, where one or more amino acids are absent from the C-terminus of the UBP. In some embodiments, the UBP is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the C-terminus of the UBP. For example, the C-terminal truncation of the UBP may be a C-terminal truncation of any UBP provided herein, such as any one of the UBPs provided in any one of SEQ ID NOs: 48-53.

It should be appreciated that other UBPs would be apparent to the skilled artisan and are within the scope of this disclosure. For example UBPs have been described previously in Sang et al., “A Unique Uracil-DNA binding protein of the uracil DNA glycosylase superfamily,” Nucleic Acids Research, Vol. 43, No. 17 2015; the entire contents of which are hereby incorporated by reference.

UDG (SEQ ID NO: 48) MIGQKTLYSFFSPSPARKRHAPSPEPAVQGTGVAGVPEESGDAAAIPAKKAPAGQEE PGTPPSSPLSAEQLDRIQRNKAAALLRLAARNVPVGFGESWKKHLSGEFGKPYFIKL MGFVAEERKHYTVYPPPHQVFTWTQMCDIKDVKVVILGQDPYHGPNQAHGLCFSV QRPVPPPPSLENIYKELSTDIEDFVHPGHGDLSGWAKQGVLLLNAVLTVRAHQANSH KERGWEQFTDAVVSWLNQNSNGLVFLLWGSYAQKKGSAIDRKRHHVLQTAHPSPL SVYRGFFGCRHFSKTNELLQKSGKKPIDWKEL UdgX (SEQ ID NO: 49) MAGAQDFVPHTADLAELAAAAGECRGCGLYRDATQAVFGAGGRSARIMMIGEQPG DKEDLAGLPFVGPAGRLLDRALEAADIDRDALYVTNAVKHFKFTRAAGGKRRIHKT PSRTEVVACRPWLIAEMTSVEPDVVVLLGATAAKALLGNDFRVTQHRGEVLHVDDV PGDPALVATVHPSSLLRGPKEERESAFAGLVDDLRVAADVRP UdgX* (R107S) (SEQ ID NO: 50) MAGAQDFVPHTADLAELAAAAGECRGCGLYRDATQAVFGAGGRSARIMMIGEQPG DKEDLAGLPFVGPAGRLLDRALEAADIDRDALYVTNAVKHFKFTRAAGGKRSIHKT PSRTEVVACRPWLIAEMTSVEPDVVVLLGATAAKALLGNDFRVTQHRGEVLHVDDV PGDPALVATVHPSSLLRGPKEERESAFAGLVDDLRVAADVRP UdgX_On (H109S) (SEQ ID NO: 51) MAGAQDFVPHTADLAELAAAAGECRGCGLYRDATQAVFGAGGRSARIMMIGEQPG DKEDLAGLPFVGPAGRLLDRALEAADIDRDALYVTNAVKHFKFTRAAGGKRRISKT PSRTEVVACRPWLIAEMTSVEPDVVVLLGATAAKALLGNDFRVTQHRGEVLHVDDV PGDPALVATVHPSSLLRGPKEERESAFAGLVDDLRVAADVRP Rev7 (SEQ ID NO: 52) MTTLTRQDLNFGQVVADVLCEFLEVAVHLILYVREVYPVGIFQKRKKYNVPVQMSC HPELNQYIQDTLHCVKPLLEKNDVEKVVVVILDKEHRPVEKFVFEITQPPLLSISSDSL LSHVEQLLRAFILKISVCDAVLDHNPPGCTFTVLVHTREAATRNMEKIQVIKDFPWIL ADEQDVHMHDPRLIPLKTMTSDILKMQLYVEERAHKGS Smug1 (SEQ ID NO: 53) MPQAFLLGSIHEPAGALMEPQPCPGSLAESFLEEELRLNAELSQLQFSEPVGIIYNPVE YAWEPHRNYVTRYCQGPKEVLFLGMNPGPFGMAQTGVPFGEVSMVRDWLGIVGPV LTPPQEHPKRPVLGLECPQSEVSGARFWGFFRNLCGQPEVFFHHCFVHNLCPLLFLAP SGRNLTPAELPAKQREQLLGICDAALCRQVQLLGVRLVVGVGRLAEQRARRALAGL MPEVQVEGLLHPSPRNPQANKGWEAVAKERLNELGLLPLLLK Nucleic Acid Polymerases (NAP)

A nucleic acid polymerase, or NAP, refers to an enzyme that synthesizes nucleic acid molecules (e.g., DNA and RNA) from nucleotides (e.g., deoxyribonucleotides and ribonucleotides). In some embodiments, the NAP is a DNA polymerase. In some embodiments, the NAP is a translesion polymerase. Translesion polymerases play a role in mutagenesis, for example, by restarting replication forks or filling in gaps that remain in the genome due to the presence of DNA lesions. Exemplary translesion polymerases include, without limitation, Pol Beta, Pol Lambda, Pol Eta, Pol Mu, Pol Iota, Pol Kappa, Pol Alpha, Pol Delta, Pol Gamma, and Pol Nu.

In some embodiments, the NAP is a eukaryotic nucleic acid polymerase. In some embodiments, the NAP is a DNA polymerase. In some embodiments, the NAP has translesion polymerase activity. In some embodiments, the NAP is a translesion DNA polymerase. In some embodiments, the NAP is a Rev7, Rev1 complex, polymerase iota, polymerase kappa, or polymerase eta. In some embodiments, the NAP is a eukaryotic polymerase alpha, beta, gamma, delta, epsilon, gamma, eta, iota, kappa, lambda, mu, or nu. In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a naturally occurring nucleic acid polymerase (e.g., a translesion DNA polymerase). In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the nucleic acid polymerases provided herein, e.g., below. For example, the NAP may comprise an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 54-64. In some embodiments, the NAP comprises the amino acid sequence of any one of SEQ ID NOs: 54-64. It should be appreciated that other NAPs would be apparent to the skilled artisan and are within the scope of this disclosure. In some embodiments, the NAP comprises the amino acid sequence of any one of SEQ ID NOs: 54-64. In some embodiments, the nucleic acid polymerase has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to any NAP provided herein, such as any one of SEQ ID NOs: 54-64.

The disclosure also provides fragments of NAPs, such as truncations of any of the NAPs provided herein. In some embodiments, the NAP is an N-terminal truncation, where one or more amino acids are absent from the N-terminus of the NAP. In some embodiments, the NAP is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the N-terminus of the NAP. For example, the N-terminal truncation of the NAP may be an N-terminal truncation of any NAP provided herein, such as any one of the NAPs provided in any one of SEQ ID NOs: 54-64. In some embodiments, the NAP is a C-terminal truncation, where one or more amino acids are absent from the C-terminus of the NAP. In some embodiments, the NAP is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the C-terminus of the NAP. For example, the C-terminal truncation of the NAP may be a C-terminal truncation of any NAP provided herein, such as any one of the NAPs provided in any one of SEQ ID NOs: 54-64.

Pol Beta (SEQ ID NO: 54) MSKRKAPQETLNGGITDMLTELANFEKNVSQAIHKYNAYRKAASVIAKYPHKIKSG AEAKKLPGVGTKIAEKIDEFLATGKLRKLEKIRQDDTSSSINFLTRVSGIGPSAARKFV DEGIKTLEDLRKNEDKLNHHQRIGLKYFGDFEKRIPREEMLQMQDIVLNEVKKVDSE YIATVCGSFRRGAESSGDMDVLLTHPSFTSESTKQPKLLHQVVEQLQKVHFITDTLSK GETKFMGVCQLPSKNDEKEYPHRRIDIRLIPKDQYYCGVLYFTGSDIFNKNMRAHAL EKGFTINEYTIRPLGVTGVAGEPLPVDSEKDIFDYIQWKYREPKDRSE Pol Lambda (SEQ ID NO: 55) MDPRGILKAFPKRQKIHADASSKVLAKIPRREEGEEAEEWLSSLRAHVVRTGIGRAR AELFEKQIVQHGGQLCPAQGPGVTHIVVDEGMDYERALRLLRLPQLPPGAQLVKSA WLSLCLQERRLVDVAGFSIFIPSRYLDHPQPSKAEQDASIPPGTHEALLQTALSPPPPP TRPVSPPQKAKEAPNTQAQPISDDEASDGEETQVSAADLEALISGHYPTSLEGDCEPS PAPAVLDKWVCAQPSSQKATNHNLHITEKLEVLAKAYSVQGDKWRALGYAKAINA LKSFHKPVTSYQEACSIPGIGKRMAEKIIEILESGHLRKLDHISESVPVLELFSNIWGAG TKTAQMWYQQGFRSLEDIRSQASLTTQQAIGLKHYSDFLERMPREEATEIEQTVQKA AQAFNSGLLCVACGSYRRGKATCGDVDVLITHPDGRSHRGIFSRLLDSLRQEGFLTD DLVSQEENGQQQKYLGVCRLPGPGRRHRRLDIIVVPYSEFACALLYFTGSAHFNRSM RALAKTKGMSLSEHALSTAVVRNTHGCKVGPGRVLPTPTEKDVFRLLGLPYREPAE RDW Pol Eta (SEQ ID NO: 56) MATGQDRVVALVDMDCFFVQVEQRQNPHLRNKPCAVVQYKSWKGGGIIAVSYEA RAFGVTRSMWADDAKKLCPDLLLAQVRESRGKANLTKYREASVEVMEEVISRFAVIE RASIDEAYVDLTSAVQERLQKLQGQPISADLLPSTYIEGLPQGPTTAEETVQKEGMRK QGLFQWLDSLQIDNLTSPDLQLTVGAVIVEEMRAAIERETGFQCSAGISHNKVLAKL ACGLNKPNRQTLVSHGSVPQLFSQMPIRK1RSLGGKLGASVIEILGIEYMGELTQFTES QLQSHFGEKNGSWLYAMCRGIEHDPVKPRQLPKTIGCSKNFPGKTALATREQVQWW LLQLAQELEERLTKDRNDNDRVATQLVVSIRVQGDKRLSSLRRCCALTRYDAHKMS HDAFTVIKNCNTSGIQTEWSPPLTMLFLCATKFSASAPSSSTDITSFLSSDPSSLPKVPV TSSEAKTQGSGPAVTATKKATTSLESFFQKAAERQKVKEASLSSLTAPTQAPMSNSPS KPSLPFQTSQSTGTEPFFKQKSLLLKQKQLNNSSVSSPQQNPWSNCKALPNSLPTEYP GCVPVCEGVSKLEESSKATPAEMDLAHNSQSMHASSASKSVLEVTQKATPNPSLLA AEDQVPCEKCGSLVPVWDMPEHMDYHFALELQKSFLQPHSSNPQVVSAVSHQGKR NPKSPLACTNKRPRPEGMQTLESFFKPLTH Pol Mu (SEQ ID NO: 57) MLPKRRRARVGSPSGDAASSTPPSTRFPGVAIYLVEPRMGRSRRAFLTGLARSKGFR VLDACSSEATHVVMEETSAEEAVSWQERRMAAAPPGCTPPALLDISWLTESLGAGQ PVPVECRHRLEVAGPRKGPLSPAWMPAYACQRPTPLTHHNTGLSEALEILAEAAGFE GSEGRLLTFCRAASVLKALPSPVTTLSQLQGLPHFGEHSSRVVQELLEHGVCEEVER VRRSERYQTMKLFTQIFGVGVKTADRWYREGLRTLDDLREQPQKLTQQQKAGLQH HQDLSTPVLRSDVDALQQVVEEAVGQALPGATVTLTGGFRRGKLQGHDVDFLITHP KEGQEAGLLPRVMCRLQDQGLILYHQHQHSCCESPTRLAQQSHMDAFERSFCIFRLP QPPGAAVGGSTRPCPSWKAVRVDLVVAPVSQFPFALLGWTGSKLFQRELRRFSRKE KGLWLNSHGLFDPEQKTFFQAASEEDIFRHLGLEYLPPEQRNA Pol Iota (SEQ ID NO: 58) MEKLGVEPEEEGGGDDDEEDAEAWAMELADVGAAASSQGVHDQVLPTPNASSRVI VHVDLDCFYAQVEMISNPELKDKPLGVQQKYLVVTCNYEARKLGVKKLMNVRDA KEKCPQLVLVNGEDLTRYREMSYKVTELLEEFSPVVERLGFDENFVDLTEMVEKRL QQLQSDELSAVTVSGHVYNNQSINLLDVLHIRLLVGSQIAAEMREAMYNQLGLTGC AGVASNKLLAKLVSGVFKPNQQTVLLPESCQHLIHSLNHIKEIPGIGYKTAKCLEALG INSVRDLQTFSPKILEKELGISVAQRIQKLSFGEDNSPVILSGPPQSFSEEDSFKKCSSEV EAKNKIEELLASLLNRVCQDGRKPHTVRLIIRRYSSEKHYGRESRQCPIPSHVIQKLGT GNYDVMTPMVDILMKLFRNMVNVKMPFHLTLLSVCFCNLKALNTAKKGLIDYYLM PSLSTTSRSGKHSFKMKDTHMEDFPKDKETNRDFLPSGRIESTRTRESPLDTTNFSKE KDINEFPLCSLPEGVDQEVFKQLPVDIQEEILSGKSREKFQGKGSVSCPLHASRGVLSF FSKKQMQDIPINPRDHLSSSKQVSSVSPCEPGTSGFNSSSSSYMSSQKDYSYYLDNRL KDERISQGPKEPQGFHFTNSNPAVSAFHSFPNLQSEQLFSRNHTTDSHKQTVATDSHE GLTENREPDSVDEKITFPSDIDPQVFYELPEAVQKELLAEWKRAGSDFHIGHK Pol Kappa (SEQ ID NO: 59) MDSTKEKCDSYKDDLLLRMGLNDNKAGMEGLDKEKINKIIMEATKGSRFYGNELK KEKQVNQRIENMMQQKAQITSQQLRKAQLQVDRFAMELEQSRNLSNTIVHIDMDAF YAAVEMRDNPELKDKPIAVGSMSMLSTSNYHARRFGVRAAMPGFIAKRLCPQLIIVP PNFDKYRAVSKEVKEILADYDPNFMAMSLDEAYLNITKHLEERQNWPEDKRRYFIK MGSSVENDNPGKEVNKLSEHERSISPLLFEESPSDVQPPGDPFQVNFEEQNNPQILQN SVVFGTSAQEVVKEIRFRIEQKTTLTASAGIAPNTMLAKVCSDKNKPNGQYQILPNRQ AVMDFIKDLPIRKVSGIGKVTEKMLKALGIITCTELYQQRALLSLLFSETSWHYFLHIS LGLGSTHLTRDGERKSMSVERTFSEINKAEEQYSLCQELCSELAQDLQKERLKGRTV TIKLKNVNFEVKTRASTVSSVVSTAEEIFAIAKELLKTEIDADFPHPLRLRLMGVRISSF PNEEDRKHQQRSIIGFLQAGNQALSATECTLEKTDKDKFVKPLEMSHKKSFFDKKRS ERKWSHQDTFKCEAVNKQSFQTSQPFQVLKKKMNENLEISENSDDCQILTCPVCFRA QGCISLEALNKHVDECLDGPSISENFKMFSCSHVSATKVNKKENVPASSLCEKQDYE AHPKIKEISSVDCIALVDTIDNSSKAESIDALSNKHSKEECSSLPSKSFNIEHCHQNSSS TVSLENEDVGSFRQEYRQPYLCEVKTGQALVCPVCNVEQKTSDLTLFNVHVDVCLN KSFIQELRKDKFNPVNQPKESSRSTGSSSGVQKAVTRTKRPGLMTKYSTSKKIKPNNP KHTLDIFFK Pol Alpha (SEQ ID NO: 60) MAPVHGDDCEIGASALSDSGSFVSSRARREKKSKKGRQEALERLKKAKAGEKYKYE VEDFTGVYEEVDEEQYSKLVQARQDDDWIVDDDGIGYVEDGREIFDDDLEDDALDA DEKGKDGKARNKDKRNVKKLAVTKPNNIKSMFIACAGKKTADKAVDLSKDGLLGD ILQDLNTETPQITPPPVMILKKKRSIGASPNPFSVHTATAVPSGKIASPVSRKEPPLTPV PLKRAEFAGDDVQVESTEEEQESGAMEFEDGDFDEPMEVEEVDLEPMAAKAWDKE SEPAEEVKQEADSGKGTVSYLGSFLPDVSCWDIDQEGDSSFSVQEVQVDSSHLPLVK GADEEQVFHFYWLDAYEDQYNQPGVVFLFGKVWIESAETHVSCCVMVKNIERTLYF LPREMKIDLNTGKETGTPISMKDVYEEFDEKIATKYKIMKFKSKPVEKNYAFEIPDVP EKSEYLEVKYSAEMPQLPQDLKGETFSHVFGTNTSSLELFLMNRKIKGPCWLEVKSP QLLNQPVSWCKVEAMALKPDLVNVIKDVSPPPLVVMAFSMKTMQNAKNHQNEIIA MAALVHHSFALDKAAPKPPFQSHFCVVSKPKDCIFPYAFKEVIEKKNVKVEVAATER TLLGFFLAKVHKIDPDIIVGHNIYGFELEVLLQRINVCKAPHWSKIGRLKRSNMPKLG GRSGFGERNATCGRMICDVEISAKELIRCKSYHLSELVQQILKTERVVIPMENIQNMY SESSQLLYLLEHTWKDAKFILQIMCELNVLPLALQITNIAGNIMSRTLMGGRSERNEF LLLHAFYENNYIVPDKQIFRKPQQKLGDEDEEIDGDTNKYKKGRKKAAYAGGLVLD PKVGFYDKFILLLDFNSLYPSIIQEFNICFTTVQRVASEAQKVTEDGEQEQIPELPDPSL EMGILPREIRKLVERRKQVKQLMKQQDLNPDLILQYDIRQKALKLTANSMYGCLGFS YSRFYAKPLAALVTYKGREILMHTKEMVQKMNLEVIYGDTDSIMINTNSTNLEEVFK LGNKVKSEVNKLYKLLEIDIDGVFKSLLLLKKKKYAALVVEPTSDGNYVTKQELKG LDIVRRDWCDLAKDTGNFVIGQILSDQSRDTIVENIQKRLIEIGENVLNGSVPVSQFEI NKALTKDPQDYPDKKSLPHVHVALWINSQGGRKVKAGDTVSYVICQDGSNLTASQR AYAPEQLQKQDNLTIDTQYYLAQQIHPVVARICEPIDGIDAVLIATWLGLDPTQFRVH HYHKDEENDALLGGPAQLTDEEKYRDCERFKCPCPTCGTENIYDNVFDGSGTDMEP SLYRCSNIDCKASPLTFTVQLSNKLIMDIRRFIKKYYDGWLICEEPTCRNRTRHLPLQF SRTGPLCPACMKATLQPEYSDKSLYTQLCFYRYIFDAECALEKLTTDHEKDKLKKQF FTPKVLQDYRKLKNTAEQFLSRSGYSEVNLSKLFAGCAVKS Pol Delta (SEQ ID NO: 61) MDGKRRPGPGPGVPPKRARGGLWDDDDAPRPSQFEEDLALMEEMEAEHRLQEQEE EELQSVLEGVADGQVPPSAIDPRWLRPTPPALDPQTEPLIFQQLEIDHYVGPAQPVPG GPPPSHGSVPVLRAFGVTDEGFSVCCHIHGFAPYFYTPAPPGFGPEHMGDLQRELNL AISRDSRGGRELTGPAVLAVELCSRESMFGYHGHGPSPFLRITVALPRLVAPARRLLE QGIRVAGLGTPSFAPYEANVDFEIRFMVDTDIVGCNWLELPAGKYALRLKEKATQCQ LEADVLWSDVVSHPPEGPWQRIAPLRVLSFDIECAGRKGIFPEPERDPVIQICSLGLRW GEPEPFLRLALTLRPCAPILGAKVQSYEKEEDLLQAWSTFIRIMDPDVITGYNIQNFDL PYLISRAQTLKVQTFPFLGRVAGLCSNIRDSSFQSKQTGRRDTKVVSMVGRVQMDM LQVLLREYKLRSYTLNAVSFHFLGEQKEDVQHSIITDLQNGNDQTRRRLAVYCLKDA YLPLRLLERLMVLVNAVEMARVTGVPLSYLLSRGQQVKVVSQLLRQAMHEGLLMP VVKSEGGEDYTGATVIEPLKGYYDVPIATLDFSSLYPSIMMAHNLCYTTLLRPGTAQ KLGLTEDQFIRTPTGDEFVKTSVRKGLLPQILENLLSARKRAKAELAKETDPLRRQVL DGRQLALKVSANSVYGFTGAQVGKLPCLEISQSVTGFGRQMIEKTKQLVESKYTVEN GYSTSAKVVYGDTDSVMCRFGVSSVAEAMALGREAADWVSGHFPSPIRLEFEKVYF PYLLISKKRYAGLLFSSRPDAHDRMDCKGLEAVRRDNCPLVANLVTASLRRLLIDRD PEGAVAHAQDVISDLLCNRIDISQLVITKELTRAASDYAGKQAHVELAERMRKRDPG SAPSLGDRVPYVIISAAKGVAAYMKSEDPLFVLEHSLPIDTQYYLEQQLAKPLLRIFEP ILGEGRAEAVLLRGDHTRCKTVLTGKVGGLLAFAKRRNCCIGCRTVLSHQGAVCEF CQPRESELYQKEVSHLNALEERFSRLWTQCQRCQGSLHEDVICTSRDCPIFYMRKKV RKDLEDQEQLLRRFGPPGPEAW Pol Gamma (SEQ ID NO: 62) MSRLLWRKVAGATVGPGPVPAPGRWVSSSVPASDPSDGQRRRQQQQQQQQQQQQ QPQQPQVLSSEGGQLRHNPLDIQMLSRGLHEQIFGQGGEMPGEAAVRRSVEHLQKH GLWGQPAVPLPDVELRLPPLYGDNLDQHFRLLAQKQSLPYLEAANLLLQAQLPPKPP AWAWAEGWTRYGPEGEAVPVAIPEERALVFDVEVCLAEGTCPTLAVAISPSAWYSW CSQRLVEERYSWTSQLSPADLIPLEVPTGASSPTQRDWQEQLVVGHNVSFDRAHIRE QYLIQGSRMRFLDTMSMHMAISGLSSFORSLWIAAKQGKHKVOPPTKQGQKSQRKA RRGPAISSWDWLDISSVNSLAEVHRLYVGGPPLEKEPRELFVKGTMKDIRENFQDLM QYCAQDVWATHEVFQQQLPLFLERCPHPVTLAGMLEMGVSYLPVNQNWERYLAEA QGTYEELQREMKKSLMDLANDACQLLSGERYKEDPWLWDLEWDLQEFKQKKAKK VKKEPATASKLPIEGAGAPGDPMDQEDLGPCSEEEEFQQDVMARACLQKLKGTTEL LPKRPQHLPGHPGWYRKLCPRLDDPAWTPGPSLLSLQMRVTPKLMALTWDGFPLHY SERHGWGYLVPGRRDNLAKLPTGTTLESAGVVCPYRAIESLYRKHCLEQGKQQLMP QEAGLAEEFLLTDNSAIWQTVEELDYLEVEAEAKMENLRAAVPGQPLALTARGGPK DTQPSYHHGNGPYNDVDIPGCWFFKLPHKDGNSCNVGSPFAKDFLPKMEDGTLQAG PGGASGPRALEINKMISFWRNAHKRISSQMVVWLPRSALPRAVIRHPDYDEEGLYGA ILPQVVTAGTITRRAVEPTWLTASNARPDRVGSELKAMVQAPPGYTLVGADVDSQE LWIAAVLGDAHFAGMHGCTAFGWMTLQGRKSRGTDLHSKTATTVGISREHAKIFNY GRIYGAGQPFAERLLMQFNHRLTQQEAAEKAQQMYAATKGLRWYRLSDEGEWLV RELNLPVDRTEGGWISLQDLRKVQRETARKSQWKKWEVVAERAWKGGTESEMFN KLESIATSDIPRTPVLGCCISRALEPSAVQEEFMTSRVNWVVQSSAVDYLHLMLVAM KWLFEEFAIDGRFCISIHDEVRYLVREEDRYRAALALQITNLLTRCMFAYKLGLNDLP QSVAFFSAVDIDRCLRKEVTMDCKTPSNPTGMERRYGIPQGEALDIYQIIELTKGSLE KRSQPGP Pol Nu (SEQ ID NO: 63) MENYEALVGFDLCNTPLSSVAQKIMSAMHSGDLVDSKTWGKSTETMEVINKSSVKY SVQLEDRKTQSPEKKDLKSLRSQTSRGSAKLSPQSFSVRLTDQLSADOKOKSISSLTL SSCLIPQYNQEASVLQKKGHKRKHFLMENINNENKGSINLKRKHITYNNLSEKTSKO MALEEDTDDAEGYLNSGNSGALKKHFCDIRHLDDWAKSQUEMLKQAAALVITym YTDGSTQLGADQTPVSSVRGIVVLVKRQAEGGHGCPDAPACGPVLEGFVSDDPCIYI QIEHSAIWDQEQEAHQQFARNVLFQTMKCKCPVICFNAKDFVRIVLQFFGNDGSWK HVADFIGLDPRIAAWLIDPSDATPSFEDLVEKYCEKSITVKVNSTYGNSSRNIVNQNV RENLKTLYRLTMDLCSKLKDYGLWQLFRTLELPLIPILAVMESHAIQVNKEEMEKTS ALLGARLKELEQEAHFVAGERFLITSNNQLREILFGKLKLHLLSQRNSLPRTGLQKYP STSEAVLNALRDLHPLPKIILEYRQVHKIKSTFVDGLLACMKKGSISSTWNQTGTVTG RLSAKHPNIQGISKHPIQITTPKNFKGKEDKILTISPRAMFVSSKGHTFLAADFSQIELRI LTHLSGDPELLKLFQESERDDVFSTLTSQWKDVPVEQVTHADREQTKKVVYAVVYG AGKERLAACLGVPIQEAAQFLESFLQKYKKIKDFARAAIAQCHQTGCVVSIMGRRRP LPRIHAHDQQLRAQAERQAVNFVVQGSAADLCKLAMIHVFTAVAASHTLTARLVAQ IHDELLFEVEDPQIPECAALVRRTMESLEQVQALELQLQVPLKVSLSAGRSWGHLVP LQEAWGPPPGPCRTESPSNSLAAPGSPASTQPPPLHFSPSFCL Rev1 (SEQ ID NO: 64) MRRGGWRKRAENDGWETWGGYMAAKVQKLEEQFRSDAAMQKDGTSSTIFSGVAI YVNGYTDPSAEELRKLMMLHGGQYHVYYSRSKTTHIIATNLPNAKIKELKGEKVIRP EWIVESIKAGRLLSYIPYQLYTKQSSVQKGLSFNPVCRPEDPLPGPSNIAKQLNNRVN HIVKKIETENEVKVNGMNSWNEEDENNDFSFVDLEQTSPGRKQNGIPHPRGSTAIFN GHTPSSNGALKTQDCLVPMVNSVASRLSPAFSQEEDKAEKSSTDFRDCTLQQLQQST RNTDALRNPHRTNSFSLSPLHSNTKINGAHHSTVQGPSSTKSTSSVSTFSKAAPSVPSK PSDCNFISNFYSHSRLHHISMWKCELTEFVNTLQRQSNGIFPGREKLKKMKTGRSALV VTDTGDMSVLNSPRHQSCIMHVDMDCFFVSVGIRNRPDLKGKPVAVTSNRGTGRAP LRPGANPQLEWQYYQNKILKGKAADIPDSSLWENPDSAQANGIDSVLSRAEIASCSY EARQLGIKNGMFFGHAKQLCPNLQAVPYDFHAYKEVAQTLYETLASYTHNIEAVSC DEALVDITEILAETKLTPDEFANAVRMEIKDQTKCAASVGIGSNILLARMATRKAKPD GQYHLKPEEVDDFIRGQLVTNLPGVGHSMESKLASLGIKTCGDLQYMTMAKLQKEF GPKTGQMLYRFCRGLDDRPVRTEKERKSVSAEINYGIRFTQPKEAEAFLLSLSEEIQR RLEATGMKGKRLTLKIMVRKPGAPVETAKFGGHGICDNIARTVTLDQATDNAKIIGK AMLNMFHTMKLNISDMRGVGIHVNQLVPTNLNPSTCPSRPSVQSSHFPSGSYSVRDV FQVQKAKKSTEEEHKEVFRAAVDLEISSASRTCTFLPPFPAHLPTSPDTNKAESSGKW NGLHTPVSVQSRLNLSIEVPSPSQLDQSVLEALPPDLREQVEQVCAVQQAESHGDKK KEPVNGCNTGILPQPVGTVLLQIPEPQESNSDAGINLIALPAFSQVDPEVFAALPAELQ RELKAAYDQRQRQGENSTHQQSASASVPKNPLLHLKAAVKEKKRNKKKKTIGSPKR IQSPLNNKLLNSPAKTLPGACGSPQKLIDGFLKHEGPPAEKPLEELSASTSGVPGLSSL QSDPAGCVRPPAPNLAGAVEFNDVKTLLREWITTISDPMEEDILQVVKYCTDLIEEKD LEKLDLVIKYMKRLMQQSVESVWNMAFDFILDNVQVVLQQTYGSTLKVT Base Excision Enzymes (BEE)

A base excision enzyme, or BEE, refers to a protein that is capable of removing a base (e.g., A, T, C, G, or U) from a nucleic acid molecule (e.g., DNA or RNA). In some embodiments, a BEE is capable of removing a cytosine from DNA. In some embodiments, a BEE is capable of removing a thymine from DNA. Exemplary BEEs include, without limitation UDG Tyr147Ala, and UDG Asn204Asp as described in Sang et al., “A Unique Uracil-DNA binding protein of the uracil DNA glycosylase superfamily,” Nucleic Acids Research, Vol. 43, No. 17 2015; the entire contents of which are hereby incorporated by reference.

In some embodiments, the base excision enzyme (BEE) is a cytosine, thymine, adenine, guanine, or uracil base excision enzyme. In some embodiments, the base excision enzyme (BEE) is a cytosine base excision enzyme. In some embodiments, the BEE is a thymine base excision enzyme. In some embodiments, the base excision enzyme comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a naturally-occurring BEE. In some embodiments, the base excision enzyme comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the BEEs provided herein, e.g., UDG (Tyr147A1a), or UDG (Asn204Asp), below. In some embodiments, the base excision enzyme comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 65-66. In some embodiments, the base excision enzyme comprises the amino acid sequence of any one of SEQ ID NOs: 65-66. In some embodiments, the base excision enzyme has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to any BEE provided herein, such as any one of SEQ ID NOs: 65-66.

The disclosure also provides fragments of BEEs, such as truncations of any of the BEEs provided herein. In some embodiments, the BEE is an N-terminal truncation, where one or more amino acids are absent from the N-terminus of the BEE. In some embodiments, the BEE is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the N-terminus of the BEE. For example, the N-terminal truncation of the BEE may be an N-terminal truncation of any BEE provided herein, such as any one of the BEEs provided in any one of SEQ ID NOs: 65-66. In some embodiments, the BEE is a C-terminal truncation, where one or more amino acids are absent from the C-terminus of the BEE. In some embodiments, the BEE is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the C-terminus of the BEE. For example, the C-terminal truncation of the BEE may be a C-terminal truncation of any BEE provided herein, such as any one of the BEEs provided in any one of SEQ ID NOs: 65-66.

It should be appreciated that other BEEs would be apparent to the skilled artisan and are within the scope of this disclosure. For example BEEs have been described previously in Sang et al., “A Unique Uracil-DNA binding protein of the uracil DNA glycosylase superfamily,” Nucleic Acids Research, Vol. 43, No. 17 2015; the entire contents of which are hereby incorporated by reference.

UDG (Tyr147Ala)-The mutated residue is indicated by bold and underlining. (SEQ ID NO: 65) MIGQKTLYSFFSPSPARKRHAPSPEPAVQGTGVAGVPEESGDAAAIPAKK APAGQEEPGTPPSSPLSAEQLDRIQRNKAAALLRLAARNVPVGFGESWKK HLSGEFGKPYFIKLMGFVAEERKHYTVYPPPHQVFTWTQMCDIKDVKVVI LGQDP A HGPNQAHGLCFSVQRPVPPPPSLENIYKELSTDIEDFVHPGHGD LSGWAKQGVLLLNAVLTVRAHQANSHKERGWEQFTDAVVSWLNQNSNGLV FLLWGSYAQKKGSAIDRKRHHVLQTAHPSPLSVYRGFFGCRHFSKTNELL QKSGKKPIDWKEL UDG (Asn204Asp)-The mutated residue is indicated by bold and underlining. (SEQ ID NO: 66) MIGQKTLYSFFSPSPARKRHAPSPEPAVQGTGVAGVPEESGDAAAIPAKK APAGQEEPGTPPSSPLSAEQLDRIQRNKAAALLRLAARNVPVGFGESWKK HLSGEFGKPYFIKLMGFVAEERKHYTVYPPPHQVFTWTQMCDIKDVKVVI LGQDPYHGPNQAHGLCFSVQRPVPPPPSLENIYKELSTDIEDFVHPGHGD LSGWAKQGVLLL D AVLTVRAHQANSHKERGWEQFTDAVVSWLNQNSNGLV FLLWGSYAQKKGSAIDRKRHHVLQTAHPSPLSVYRGFFGCRHFSKTNELL QKSGKKPIDWKEL Deaminase Domains

In some embodiments, any of the fusion proteins or base editors provided herein comprise a cytidine deaminase domain. In some embodiments, the cytidine deaminase domain can catalyze a C to U base change. In some embodiments, the cytidine deaminase domain is an apolipoprotein B mRNA-editing complex (APOBEC) family deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC1 deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC2 deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3 deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3A deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3B deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3C deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3D deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3E deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3F deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3G deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC3H deaminase. In some embodiments, the cytidine deaminase domain is an APOBEC4 deaminase. In some embodiments, the cytidine deaminase domain is an activation-induced deaminase (AID). In some embodiments, the cytidine deaminase domain is a vertebrate deaminase. In some embodiments, the cytidine deaminase domain is an invertebrate deaminase. In some embodiments, the cytidine deaminase domain is a human, chimpanzee, gorilla, monkey, cow, dog, rat, or mouse deaminase. In some embodiments, the cytidine deaminase domain is a human deaminase. In some embodiments, the cytidine deaminase domain is a rat deaminase, e.g., rAPOBEC1. In some embodiments, the cytidine deaminase domain is a Petromyzon marinus cytidine deaminase 1 (pmCDA1). In some embodiments, the cytidine deaminase domain is a human APOBEC3G (SEQ ID NO: 77). In some embodiments, the cytidine deaminase domain is a fragment of the human APOBEC3G (SEQ ID NO: 100). In some embodiments, the cytidine deaminase domain is a human APOBEC3G variant comprising a D316R_D317R mutation (SEQ ID NO: 99). In some embodiments, the cytidine deaminase domain is a frantment of the human APOBEC3G and comprising mutations corresponding to the D316R_D317R mutations in SEQ ID NO: 77 (SEQ ID NO: 101).

In some embodiments, the cytidine deaminase domain is at least 80%, at least 85%, at least 90%, at least 92%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to a naturally-occurring cytidine deaminase. In some embodiments, the cytidine deaminase domain is at least 80%, at least 85%, at least 90%, at least 92%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to any of the cytidine deaminases provided herein. In some embodiments, the cytidine deaminase domain is at least 80%, at least 85%, at least 90%, at least 92%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 99.5% identical to the deaminase domain of any one of SEQ ID NOs: 67-101. In some embodiments, the nucleic acid editing domain comprises the amino acid sequence of any one of SEQ ID NOs: 67-101. In some embodiments, the cytidine deaminase domain has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, or more amino acid changes compared to any cytidine deaminase domain provided herein, such as any one of SEQ ID NOs: 67-101.

The disclosure also provides fragments of cytidine deaminase domains, such as truncations of any of the cytidine deaminase domains provided herein. In some embodiments, the cytidine deaminase domain is an N-terminal truncation, where one or more amino acids are absent from the N-terminus of the cytidine deaminase domain. In some embodiments, the cytidine deaminase domain is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the N-terminus of the cytidine deaminase domain. For example, the N-terminal truncation of the cytidine deaminase domain may be an N-terminal truncation of any cytidine deaminase domain provided herein, such as any one of the cytidine deaminase domains provided in any one of SEQ ID NOs: 67-101. In some embodiments, the cytidine deaminase domain is a C-terminal truncation, where one or more amino acids are absent from the C-terminus of the cytidine deaminase domain. In some embodiments, the cytidine deaminase domain is absent 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 amino acids from the C-terminus of the cytidine deaminase domain. For example, the C-terminal truncation of the cytidine deaminase domain may be a C-terminal truncation of any cytidine deaminase domain provided herein, such as any one of the cytidine deaminase domains provided in any one of SEQ ID NOs: 67-101.

Some exemplary cytidine deaminase domains include, without limitation, those provided below. It should be understood that, in some embodiments, the active domain of the respective sequence can be used, e.g., the domain without a localizing signal (nuclear localization sequence, without nuclear export signal, cytoplasmic localizing signal).

Human AID: MDSLLMNRRKFLYQFKNVRWAKGRRETYLCYVVKRRDSATSFSLDFGYLRNKNGC HVELLFLRYISDWDLDPGRCYRVTWFTSWSPCYDCARHVADFLRGNPNLSLRIFTAR LYFCEDRKAEPEGLRRLHRAGVQIAIMTFKDYFYCWNTFVENHERTFKAWEGLHEN SVRLSRQLRRILLPLYEVDDLRDAFRTLGL (SEQ ID NO: 67) (underline: nuclear localization sequence; double underline: nuclear export signal)

Human AID: (SEQ ID NO: 67) MDSLLMNRRKFLYQFKNVRWAKGRRETYLCYVVKRRDSATSFSLDFGYLRNKNGC HVELLFLRYISDWDLDPGRCYRVTWFTSWSPCYDCARHVADFLRGNPNLSLRIFTAR LYFCEDRKAEPEGLRRLHRAGVQIAIMTFKDYFYCWNTFVENHERTFKAWEGLHEN SVRLSRQLRRILLPLYEVDDLRDAFRTLGL (underline: nuclear localization sequence; double underline: nuclear export signal) Mouse AID: (SEQ ID NO: 68) MDSLLMKQKKFLYHFKNVRWAKGRHETYLCYVVKRRDSATSCSLDFGHLRNKSGC HVELLFLRYISDWDLDPGRCYRVTWFTSWSPCYDCARHVAEFLRWNPNLSLRIFTAR LYFCEDRKAEPEGLRRLHRAGVQIGIMTFKDYFYCWNTFVENRERTFKAWEGLHEN SVRLTRQLRRILLPLYEVDDLRDAFRMLGF (underline: nuclear localization sequence; double underline: nuclear export signal) Dog AID: (SEQ ID NO: 69) MDSLLMKQRKFLYHFKNVRWAKGRHETYLCYVVKRRDSATSFSLDFGHLRNKSGC HVELLFLRYISDWDLDPGRCYRVTWFTSWSPCYDCARHVADFLRGYPNLSLRIFAAR LYFCEDRKAEPEGLRRLHRAGVQIAIMTFKDYFYCWNTFVENREKTFKAWEGLHEN SVRLSRQLRRILLPLYEVDDLRDAFRTLGL (underline: nuclear localization sequence; double underline: nuclear export signal) Bovine AID: (SEQ ID NO: 70) MDSLLKKQRQFLYQFKNVRWAKGRHETYLCYVVKRRDSPTSFSLDFGHLRNKAGC HVELLFLRYISDWDLDPGRCYRVTWFTSWSPCYDCARHVADFLRGYPNLSLRIFTAR LYFCDKERKAEPEGLRRLHRAGVQIAIMTFKDYFYCWNTFVENHERTFKAWEGLHE NSVRLSRQLRRILLPLYEVDDLRDAFRTLGL (underline: nuclear localization sequence; double underline: nuclear export signal) Rat AID (SEQ ID NO: 71) MAVGSKPKAALVGPHWERERIWCFLCSTGLGTQQTGQTSRWLRPAATQDPVSPPRS LLMKQRKFLYHFKNVRWAKGRHETYLCYVVKRRDSATSFSLDFGYLRNKSGCHVE LLFLRYISDWDLDPGRCYRVTWFTSWSPCYDCARHVADFLRGNPNLSLRIFTARLTG WGALPAGLMSPARPSDYFYCWNTFVENHERTFKAWEGLHENSVRLSRRLRRILLPL YEVDDLRDAFRTLGL (underline: nuclear localization sequence; double underline: nuclear export signal) Mouse APOBEC-3: (SEQ ID NO: 72) MGPFCLGCSHRKCYSPIRNLISQETFKFHFKNLGYAKGRKDTFLCYEVTRKDCDSPV SLHHGVFKNKDNIHAEICFLYWFHDKVLKVLSPREEFKITWYMSWSPCFECAEQIVRFL ATHHNLSLDIFSSRLYNVQDPETQQNLCRLVQEGAQVAAMDLYEFKKCWKKFVDN GGRRFRPWKRLLTNFRYQDSKLQEILRPCYIPVPSSSSSTLSNICLTKGLPETRFCVEG RRMDPLSEEEFYSQFYNQRVKHLCYYHRMKPYLCYQLEQFNGQAPLKGCLLSEKGK QHAEILFLDKIRSMELSQVTITCYLTWSPCPNCAWQLAAFKRDRPDLILHIYTSRLYFHW KRPFQKGLCSLWQSGILVDVMDLPQFTDCWTNFVNPKRPFWPWKGLEIISRRTQRRL RRIKESWGLQDLVNDFGNLQLGPPMS (italic: nucleic acid editing domain) Rat APOBEC-3: (SEQ ID NO: 73) MGPFCLGCSHRKCYSPIRNLISQETFKFHFKNLRYAIDRKDTFLCYEVTRKDCDSPVS LHHGVFKNKDNIHAEICFLYWFHDKVLKVLSPREEFKITWYMSWSPCFECAEQVLRFLA THHNLSLDIFSSRLYNIRDPENQQNLCRLVQEGAQVAAMDLYEFKKCWKKFVDNGG RRFRPWKKLLTNFRYQDSKLQEILRPCYIPVPSSSSSTLSNICLTKGLPETRFCVERRR VHLLSEEEFYSQFYNQRVKHLCYYHGVKPYLCYQLEQFNGQAPLKGCLLSEKGKQH AEILFLDKIRSMELSQVIITCYLTWSPCPNCAWQLAAFKRDRPDLILHIYTSRLYFHWKR PFQKGLCSLWQSGILVDVMDLPQFTDCWTNFVNPKRPFWPWKGLEIISRRTQRRLHR IKESWGLQDLVNDFGNLQLGPPMS (italic: nucleic acid editing domain) Rhesus macaque APOBEC-3G: (SEQ ID NO: 74) MVEPMDPRTFVSNFNNRPILSGLNTVWLCCEVKTKDPSGPPLDAKIFQGKVYSKAKY HPEM RFLRWFHKWRQLHHDQEYKVTWYVSWSPCTRCANSVATFLAKDPKVTLTIFVA RLYYFWKPDYQQALRILCQKRGGPHATMKIMNYNEFQDCWNKFVDGRGKPFKPRN NLPKHYTLLQATLGELLRHLMDPGTFTSNFNNKPWVSGQHETYLCYKVERLHNDT WVPLNQHRGFLRNQAPNIHGFPKGRHAELCFLDLIPFWKLDGQQYRVTCFTSWSPCFS CAQEMAKFISNNEHVSLCIFAARIYDDQGRYQEGLRALHRDGAKIAMMNYSEFEYC WDTFVDRQGRPFQPWDGLDEHSQALSGRLRAI (italic: nucleic acid editing domain; underline: cytoplasmic localization signal) Chimpanzee APOBEC-3 G: (SEQ ID NO: 75) MKPHFRNPVERMYQDTFSDNFYNRPILSHRNTVWLCYEVKTKGPSRPPLDAKIFRGQ VYSKLKYHPEMRFFHWFSKWRKLHRDQEYEVIWYISWSPCTKCTRDVATFLAEDPKV TLTIFVARLYYFWDPDYQEALRSLCQKRDGPRATMKININYDEFQHCWSKFVYSQRE LFEPWNNLPKYYILLHIEVILGEILRHSMDPPTFTSNFNNELWVRGRHETYLCYEVERL HNDTWVLLNQRRGFLCNQAPHKHGFLEGRHAELCFLDVIPFWKLDLHQDYRVTCFTS WSPCFSCAQEMAKFISNNKHVSLCIFAARIYDDQGRCQEGLRTLAKAGAKISIMTYSE FKHCWDTFVDHQGCPFQPWDGLEEHSQALSGRLRAILQNQGN (italic: nucleic acid editing domain; underline: cytoplasmic localization signal) Green monkey APOBEC-3G: (SEQ ID NO: 76) MNPQIRNMVEQMEPDIFVYYFNNRPILSGRNTVWLCYEVKTKDPSGPPLDANIFQGK LYPEAKDHPEMKFLHWFRKWRQLHRDQEYEVTWYVSWSPCTRCANSVATFLAEDPKV TLTIFVARLYYFWKPDYQQALRILCQERGGPHATMKIMNYNEFQHCWNEFVDGQG KPFKPRKNLPKHYTLLHATLGELLRHVMDPGTFTSNFNNKPWVSGQRETYLCYKVE RSHNDTWVLLNQHRGFLRNQAPDRHGFPKGRHAELCFLDLIPFWKLDDQQYRVTCFT SWSPCFSCAQKMAKFISNNKHVSLCIFAARIYDDQGRCQEGLRTLHRDGAKIAVMNY SEFEYCWDTFVDRQGRPFQPWDGLDEHSQALSGRLRAI (italic: nucleic acid editing domain; underline: cytoplasmic localization signal) Human APOBEC-3G: (SEQ ID NO: 77) MKPHFRNTVERMYRDTFSYNFYNRPILSRRNTVWLCYEVKTKGPSRPPLDAKIFRGQ VYSELKYHPEMRFFHWFSKWRKLHRDQEYEVTWYISWSPCTKCTRDMATFLAEDPKV TLTIFVARLYYFWDPDYQEALRSLCQKRDGPRATMKEVINYDEFQHCWSKFVYSQRE LFEPWNNLPKYYILLHIIVILGEILRHSMDPPTFTFNFNNEPWVRGRHETYLCYEVERM HNDTWVLLNQRRGFLCNQAPHKHGFLEGRHAELCFLDVIPFWKLDLDQDYRVTCFTS WSPCFSCAQEMAKFISKNKHVSLCIFTARIYDDQGRCQEGLRTLAEAGAKISIMTYSE FKHCWDTFVDHQGCPFQPWDGLDEHSQDLSGRLRAILQNQEN (italic: nucleic acid editing domain; underline: cytoplasmic localization signal) Human APOBEC-3F: (SEQ ID NO: 78) MKPHFRNTVERMYRDTFSYNFYNRPILSRRNTVWLCYEVKTKGPSRPRLDAKIFRGQ VYSQPEHHAEMCFLSWFCGNQLPAYKCFQIIWFVSWTPCPDCVAKLAEFLAEHPNVTL TISAARLYYYWERDYRRALCRLSQAGARVKIMDDEEFAYCWENFVYSEGQPFMPW YKFDDNYAFLHRTLKEILRNPMEAMYPHIFYFHFKNLRKAYGRNESWLCFTMEVVK HHSPVSWKRGVFRNQVDPETHCHAERCFLSWFCDDILSPNTNYEVTWYTSWSPCPECA GEVAEFLARHSNVNLTIFTARLYYFWDTDYQEGLRSLSQEGASVEIMGYKDFKYCW ENFVYNDDEPFKPWKGLKYNFLFLDSKLQEILE (italic: nucleic acid editing domain) Human APOBEC-3B: (SEQ ID NO: 79) MNPQIRNPMERMYRDTFYDNFENEPILYGRSYTWLCYEVKIKRGRSNLLWDTGVFR GQVYFKPQYHAEMCFLSWFCGNQLPAYKCFQITWFVSWIPCPDCVAKLAEFLSEHPN VTLTISAARLYYYWERDYRRALCRLSQAGARVTIMDYEEFAYCWENFVYNEGQQF MPWYKFDENYAFLHRTLKEILRYLMDPDTFTFNFNNDPLVLRRRQTYLCYEVERLD NGTWVLMDQHMGFLCNEAKNLLCGFYGRHAELRFLDLVPSLQLDPAQIYRVIWFISWS PCFSWGCAGEVRAFLQENTHVRLRIFAARIYDYDPLYKEALQMLRDAGAQVSIMTY DEFEYCWDTFVYRQGCPFQPWDGLEEHSQALSGRLRAILQNQGN (italic: nucleic acid editing domain) Rat APOBEC3: (SEQ ID NO: 80) MQPQGLGPNAGMGPVCLGCSHRRPYSPIRNPLKKLYQQTFYFHFKNVRYAWGRKN NFLCYEVNGMDCALPVPLRQGVFRKQGHIHAELCFIYWFHDKVLRVLSPMEEFKVT WYMSWSPCSKCAEQVARFLAAHRNLSLAIFSSRLYYYLRNPNYQQKLCRLIQEGVH VAAMDLPEFKKCWNKFVDNDGQPFRPWMRLRINFSFYDCKLQEIFSRMNLLREDVF YLQFNNSHRVKPVQNRYYRRKSYLCYQLERANGQEPLKGYLLYKKGEQHVEILFLE KMRSMELSQVRITCYLTWSPCPNCARQLAAFKKDHPDLILRIYTSRLYFYWRKKFQK GLCTLWRSGIHVDVMDLPQFADCWTNFVNPQRPFRPWNELEKNSWRIQRRLRRIKE SWGL Bovine APOBEC-3B: (SEQ ID NO: 81) DGWEVAFRSGTVLKAGVLGVSMTEGWAGSGHPGQGACVWTPGTRNTMNLLREVL FKQQFGNQPRVPAPYYRRKTYLCYQLKQRNDLTLDRGCFRNKKQRHAEIRFIDKINS LDLNPSQSYKIICYITWSPCPNCANELVNFITRNNHLKLEIFASRLYFHWIKSFKMGLQ DLQNAGISVAVMTHTEFEDCWEQFVDNQSRPFQPWDKLEQYSASIRRRLQRILTAPI Chimpanzee APOB EC-3B: (SEQ ID NO: 82) MNPQIRNPMEWMYQRTFYYNFENEPILYGRSYTWLCYEVKIRRGHSNLLWDTGVFR GQMYSQPEHHAEMCFLSWFCGNQLSAYKCFQITWFVSWTPCPDCVAKLAKFLAEH PNVTLTISAARLYYYWERDYRRALCRLSQAGARVKIMDDEEFAYCWENFVYNEGQP FMPWYKFDDNYAFLHRTLKEIIRHLMDPDTFTFNFNNDPLVLRRHQTYLCYEVERLD NGTWVLMDQHMGFLCNEAKNLLCGFYGRHAELRFLDLVPSLQLDPAQIYRVTWFIS WSPCFSWGCAGQVRAFLQENTHVRLRIFAARIYDYDPLYKEALQMLRDAGAQVSIM TYDEFEYCWDTFVYRQGCPFQPWDGLEEHSQALSGRLRAILQVRASSLCMVPHRPPP PPQSPGPCLPLCSEPPLGSLLPTGRPAPSLPFLLTASFSFPPPASLPPLPSLSLSPGHLPVP SFHSLTSCSIQPPCSSRIRETEGWASVSKEGRDLG Human APOBEC-3C: (SEQ ID NO: 83) MNPQIRNPMKAMYPGTFYFQFKNLWEANDRNETWLCFTVEGIKRRSVVSWKTGVF RNQVDSETHCHAERCFLSWFCDDILSPNTKYQVIWYTSWSPCPDCAGEVAEFLARHSN VNLTIFTARLYYFQYPCYQEGLRSLSQEGVAVEIMDYEDFKYCWENFVYNDNEPFKP WKGLKTNFRLLKRRLRESLQ (italic: nucleic acid editing domain) Gorilla APOBEC3C (SEQ ID NO: 84) MNPQIRNPMKAMYPGTFYFQFKNLWEANDRNETWLCFTVEGIKRRSVVSWKTGVF RNQVDSETHCHAERCFLSWFCDDILSPNTNYQVIWYTSWSPCPECAGEVAEFLARHSN VNLTIFTARLYYFQDTDYQEGLRSLSQEGVAVKIMDYKDFKYCWENFVYNDDEPFK PWKGLKYNFRFLKRRLQEILE (italic: nucleic acid editing domain) Human APOB EC-3A: (SEQ ID NO: 85) MEASPASGPRHLMDPHIFTSNFNNGIGRHKTYLCYEVERLDNGTSVKMDQHRGFLH NQAKNLLCGFYGRHAELRFLDLVPSLQLDPAQIYRVTWFISWSPCFSWGCAGEVRAFLQ ENTHVRLRIFAARIYDYDPLYKEALQMLRDAGAQVSIMTYDEFKHCWDTFVDHQGC PFQPWDGLDEHSQALSGRLRAILQNQGN (italic: nucleic acid editing domain) Rhesus macaque APOBEC-3A: (SEQ ID NO: 86) MDGSPASRPRHLMDPNTFTFNFNNDLSVRGRHQTYLCYEVERLDNGTWVPMDERR GFLCNKAKNVPCGDYGCHVELRFLCEVPSWQLDPAQTYRVIWFISWSPCFRRGCAGQ VRVFLQENKHVRLRIFAARIYDYDPLYQEALRTLRDAGAQVSIMTYEEFKHCWDTF VDRQGRPFQPWDGLDEHSQALSGRLRAILQNQGN (italic: nucleic acid editing domain) Bovine APOBEC-3A: (SEQ ID NO: 87) MDEYTFTENFNNQGWPSKTYLCYEMERLDGDATIPLDEYKGFVRNKGLDQPEKPCH AELYFLGKIHSWNLDRNQHYRLTCFISWSPCYDCAQKLTTFLKENHHISLHILASRIYTH NRFGCHQSGLCELQAAGARITIMTFEDFKHCWETFVDHKGKPFQPWEGLNVKSQAL CTELQAILKTQQN (italic: nucleic acid editing domain) Human APOBEC-3H: (SEQ ID NO: 88) MALLTAETFRLQFNNKRRLRRPYYPRKALLCYQLTPQNGSTPTRGYFENKKKCHAEI CFINEIKSMGLDETQCYQVTCYLTWSPCSSCAWELVDFIKAHDHLNLGIFASRLYYHWC KPQQKGLRLLCGSQVPVEVMGFPKFADCWENFVDHEKPLSFNPYKMLEELDKNSRA IKRRLERIKIPGVRAQGRYMDILCDAEV (italic: nucleic acid editing domain) Rhesus macaque APOBEC-3H: (SEQ ID NO: 89) MALLTAKTFSLQFNNKRRVNKPYYPRKALLCYQLTPQNGSTPTRGHLKNKKKDHAE IRFINKIKSMGLDETQCYQVTCYLTWSPCPSCAGELVDFIKAHRHLNLRIFASRLYYH WRPNYQEGLLLLCGSQVPVEVMGLPEFTDCWENFVDHKEPPSFNPSEKLEELDKNS QAIKRRLERIKSRSVDVLENGLRSLQLGPVTPSSSIRNSR Human APOBEC-3D: (SEQ ID NO: 90) MNPQRNPMERMYRDTFYDNFENEPILYGRSYTWLCYEVKIKRGRSNLLWDTGVFR GPVLPKRQSNHRQEVYFRFENHAEMCFLSWFCGNRLPANRRFQITWFVSWNPCLPCVV KVTKFLAEHPNVTLTISAARLYYYRDRDWRWVLLRLHKAGARVKIMDYEDFAYCW ENFVCNEGQPFMPWYKFDDNYASLHRTLKEILRNPMEAMYPHIFYFHFKNLLKACG RNESWLCFTMEVTKHHSAVFRKRGVFRNQVDPETHCHAERCFLSWFCDDILSPNTNY EVTWYTSWSPCPECAGEVAEFLARHSNVNLTIFTARLCYFWDTDYQEGLCSLSQEGAS VKIMGYKDFVSCWKNFVYSDDEPFKPWKGLQTNFRLLKRRLREILQ (italic: nucleic acid editing domain) Human APOBEC-1: (SEQ ID NO: 91) MTSEKGPSTGDPTLRRRIEPWEFDVFYDPRELRKEACLLYEIKWGMSRKIWRSSGKN TTNHVEVNFIKKFTSERDFHPSMSCSITWFLSWSPCWECSQAIREFLSRHPGVTLVIYV ARLFWHMDQQNRQGLRDLVNSGVTIQIIVIRASEYYHCWRNFVNYPPGDEAHWPQY PPLWMMLYALELHCIILSLPPCLKISRRWQNHLTFFRLHLQNCHYQTIPPHILLATGLI HPSVAWR Mouse APOBEC-1: (SEQ ID NO: 92) MSSETGPVAVDPTLRRRIEPHEFEVFFDPRELRKETCLLYEINWGGRHSVWRHTSQN TSNHVEVNFLEKFTTERYFRPNTRCSITWFLSWSPCGECSRAITEFLSRHPYVTLFIYIA RLYHHTDQRNRQGLRDLISSGVTIQIMTEQEYCYCWRNFVNYPPSNEAYWPRYPHL WVKLYVLELYCIILGLPPCLKILRRKQPQLTFFTITLQTCHYQRIPPHLLWATGLK Rat APOBEC-1: (SEQ ID NO: 93) MSSETGPVAVDPTLRRRIEPHEFEVFFDPRELRKETCLLYEINWGGRHSIWRHTSQNT NKHVEVNFIEKFTTERYFCPNTRCSITWFLSWSPCGECSRAITEFLSRYPHVTLFIYIAR LYHHADPRNRQGLRDLISSGVTIQIMTEQESGYCWRNFVNYSPSNEAHWPRYPHLW VRLYVLELYCIILGLPPCLNILRRKQPQLTFFTIALQSCHYQRLPPHILWATGLK Human APOBEC-2: (SEQ ID NO: 94) MAQKEEAAVATEAASQNGEDLENLDDPEKLKELIELPPFEIVTGERLPANFFKFQFRN VEYSSGRNKTFLCYVVEAQGKGGQVQASRGYLEDEHAAAHAEEAFFNTILPAFDPA LRYNVTWYVSSSPCAACADRIIKTLSKTKNLRLLILVGRLFMWEEPEIQAALKKLKE AGCKLRIMKPQDFEYVWQNFVEQEEGESKAFQPWEDIQENFLYYEEKLADILK Mouse APOBEC-2: (SEQ ID NO: 95) MAQKEEAAEAAAPASQNGDDLENLEDPEKLKELIDLPPFEIVTGVRLPVNFFKFQFR NVEYSSGRNKTFLCYVVEVQSKGGQAQATQGYLEDEHAGAHAEEAFFNTILPAFDP ALKYNVTWYVSSSPCAACADRILKTLSKTKNLRLLILVSRLFMWEEPEVQAALKKLK EAGCKLRIMKPQDFEYIWQNFVEQEEGESKAFEPWEDIQENFLYYEEKLADILK Rat APOBEC-2: (SEQ ID NO: 96) MAQKEEAAEAAAPASQNGDDLENLEDPEKLKELIDLPPFEIVTGVRLPVNFFKFQFR NVEYSSGRNKTFLCYVVEAQSKGGQVQATQGYLEDEHAGAHAEEAFFNTILPAFDP ALKYNVTWYVSSSPCAACADRILKTLSKTKNLRLLILVSRLFMWEEPEVQAALKKLK EAGCKLRIMKPQDFEYLWQNFVEQEEGESKAFEPWEDIQENFLYYEEKLADILK Bovine APOBEC-2: (SEQ ID NO: 97) MAQKEEAAAAAEPASQNGEEVENLEDPEKLKELIELPPFEIVTGERLPAHYFKFQFRN VEYSSGRNKTFLCYVVEAQSKGGQVQASRGYLEDEHATNHAEEAFFNSIMPTFDPA LRYMVTWYVSSSPCAACADRIVKTLNKTKNLRLLILVGRLFMWEEPEIQAALRKLKE AGCRLRIMKPQDFEYIWQNFVEQEEGESKAFEPWEDIQENFLYYEEKLADILK Petromyzon marinus CDA1 (pmCDA1) (SEQ ID NO: 98) MTDAEYVRIHEKLDIYTFKKQFFNNKKSVSHRCYVLFELKRRGERRACFWGYAVNK PQSGTERGIHAEIFSIRKVEEYLRDNPGQFTINWYSSWSPCADCAEKILEWYNQELRG NGHTLKIWACKLYYEKNARNQIGLWNLRDNGVGLNVMVSEHYQCCRKIFIQSSHNQ LNENRWLEKTLKRAEKRRSELSIMIQVKILHTTKSPAV Human APOBEC3G D316R D317R (SEQ ID NO: 99) MKPHFRNTVERMYRDTFSYNFYNRPILSRRNTVWLCYEVKTKGPSRPPLDAKIFRGQ VYSELKYHPEMRFFHWFSKWRKLHRDQEYEVTWYISWSPCTKCTRDMATFLAEDP KVTLTIFVARLYYFWDPDYQEALRSLCQKRDGPRATMKIMNYDEFQHCWSKFVYS QRELFEPWNNLPKYYILLHIMLGEILRHSMDPPTFTFNFNNEPWVRGRHETYLCYEV ERMHNDTWVLLNQRRGFLCNQAPHKHGFLEGRHAELCFLDVIPFWKLDLDQDYRV TCFTSWSPCFSCAQEMAKFISKNKHVSLCIFTARIYRRQGRCQEGLRTLAEAGAKISI MTYSEFKHCWDTFVDHQGCPFQPWDGLDEHSQDLSGRLRAILQNQEN Human APOBEC3G chain A (SEQ ID NO: 100) MDPPTFTFNFNNEPWVRGRHETYLCYEVERMHNDTWVLLNQRRGFLCNQAPHKHG FLEGRHAELCFLDVIPFWKLDLDQDYRVTCFTSWSPCFSCAQEMAKFISKNKHVSLCI FTARIYDDQGRCQEGLRTLAEAGAKISIMTYSEFKHCWDTFVDHQGCPFQPWDGLD EHSQDLSGRLRAILQ Human APOBEC3G chain A D120R D121R (SEQ ID NO: 101) MDPPTFTFNFNNEPWVRGRHETYLCYEVERMHNDTWVLLNQRRGFLCNQAPHKHG FLEGRHAELCFLDVIPFWKLDLDQDYRVTCFTSWSPCFSCAQEMAKFISKNKHVSLCI FTARIYRRQGRCQEGLRTLAEAGAKISIMTYSEFKHCWDTFVDHQGCPFQPWDGLDE HSQDLSGRLRAILQ Deaminase Domains that Modulate the Editing Window of Base Editors

Some aspects of the disclosure are based on the recognition that modulating the deaminase domain catalytic activity of any of the fusion proteins provided herein, for example by making point mutations in the deaminase domain, affect the processivity of the fusion proteins (e.g., base editors). For example, mutations that reduce, but do not eliminate, the catalytic activity of a deaminase domain within a base editing fusion protein can make it less likely that the deaminase domain will catalyze the deamination of a residue adjacent to a target residue, thereby narrowing the deamination window. The ability to narrow the deaminataion window may prevent unwanted deamination of residues adjacent of specific target residues, which may decrease or prevent off-target effects.

In some embodiments, any of the fusion proteins provided herein comprise a deaminase domain (e.g., a cytidine deaminase domain) that has reduced catalytic deaminase activity. In some embodiments, any of the fusion proteins provided herein comprise a deaminase domain (e.g., a cytidine deaminase domain) that has a reduced catalytic deaminase activity as compared to an appropriate control. For example, the appropriate control may be the deaminase activity of the deaminase prior to introducing one or more mutations into the deaminase. In other embodiments, the appropriate control may be a wild-type deaminase. In some embodiments, the appropriate control is a wild-type apolipoprotein B mRNA-editing complex (APOBEC) family deaminase. In some embodiments, the appropriate control is an APOBEC1 deaminase, an APOBEC2 deaminase, an APOBEC3A deaminase, an APOBEC3B deaminase, an APOBEC3C deaminase, an APOBEC3D deaminase, an APOBEC3F deaminase, an APOBEC3G deaminase, or an APOBEC3H deaminase. In some embodiments, the appropriate control is an activation induced deaminase (AID). In some embodiments, the appropriate control is a cytidine deaminase 1 from Petromyzon marinus (pmCDA1). In some embodiments, the deaminase domain may be a deaminase domain that has at least 1%, at least 5%, at least 15%, at least 20%, at least 25%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% less catalytic deaminase activity as compared to an appropriate control.

In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising one or more mutations selected from the group consisting of H121X, H122X, R126X, R126X, R118X, W90X, W90X, and R132X of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase, wherein X is any amino acid. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising one or more mutations selected from the group consisting of H121R, H122R, R126A, R126E, R118A, W90A, W90Y, and R132E of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase.

In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising one or more mutations selected from the group consisting of D316X, D317X, R320X, R320X, R313X, W285X, W285X, R326X of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase, wherein X is any amino acid. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising one or more mutations selected from the group consisting of D316R, D317R, R320A, R320E, R313A, W285A, W285Y, R326E of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase.

In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a H121R and a H122 Rmutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R126A mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R126E mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R118A mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W90A mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W90Y mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R132E mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W90Y and a R126E mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R126E and a R132E mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W90Y and a R132E mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W90Y, R126E, and R132E mutation of rAPOBEC1 (SEQ ID NO: 93), or one or more corresponding mutations in another APOBEC deaminase.

In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a D316R and a D317R mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R320A mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R320E mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R313A mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W285A mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W285Y mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R326E mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W285Y and a R320E mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a R320E and a R326E mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W285Y and a R326E mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase. In some embodiments, any of the fusion proteins provided herein comprise an APOBEC deaminase comprising a W285Y, R320E, and R326E mutation of hAPOBEC3G (SEQ ID NO: 77), or one or more corresponding mutations in another APOBEC deaminase.

Fusion Proteins Comprising a Nuclease Programmable DNA Binding Protein (napDNAbp), a Cytidine Deaminase, and a Uracil Binding Protein (UBP)

Some aspects of the disclosure provide fusion proteins comprising a nucleic acid programmable DNA binding protein (napDNAbp), a cytidine deaminase, and a uracil binding protein (UBP). In some embodiments, any of the fusion proteins provided herein are base editors. In some embodiments, the UBP is a uracil modifying enzyme. In some embodiments, the UBP is a uracil base excision enzyme. In some embodiments, the UBP is a uracil DNA glycosylase. In some embodiments, the UBP is any of the uracil binding proteins provided herein. For example, the UBP may be a UDG, a UdgX, a UdgX*, a UdgX_On, or a SMUG1. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a uracil binding protein, a uracil base excision enzyme or a uracil DNA glycosylase (UDG) enzyme. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the uracil binding proteins provided herein. For example, the UBP may comprise an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 48-53. In some embodiments, the UBP comprises the amino acid sequence of any one of SEQ ID NOs: 48-53.

In some embodiments, the napDNAbp is a Cas9 domain, a Cpf1 domain, a CasX domain, a CasY domain, a C2c1 domain, a C2c2 domain, aC2c3 domain, or an Argonaute domain. In some embodiments, the napDNAbp is any napDNAbp provided herein. In some embodiments, the napDNAbp of any of the fusion proteins provided herein is a Cas9 domain. The Cas9 domain may be any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein. In some embodiments, any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein may be fused with any of the cytidine deaminases provided herein. In some embodiments, the fusion protein comprises the structure:

-   -   NH₂-[cytidine deaminase]-[napDNAbp]-[UBP]-COOH;     -   NH₂-[cytidine deaminase]-[UBP]-[napDNAbp]-COOH;     -   NH₂-[UBP]-[cytidine deaminase]-[napDNAbp]-COOH;     -   NH₂-[UBP]-[napDNAbp]-[cytidine deaminase]-COOH;     -   NH₂-[napDNAbp]-[UBP]-[cytidine deaminase]-COOH; or     -   NH₂-[napDNAbp]-[cytidine deaminase]-[UBP]-COOH

In some embodiments, the fusion proteins comprising a cytidine deaminase, a napDNAbp (e.g., Cas9 domain), and UBP do not include a linker sequence. In some embodiments, a linker is present between the cytidine deaminase domain and the napDNAbp. In some embodiments, a linker is present between the cytidine deaminase domain and the UBP. In some embodiments, a linker is present between the napDNAbp and the UBP. In some embodiments, the “-” used in the general architecture above indicates the presence of an optional linker. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via any of the linkers provided herein. For example, in some embodiments the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via any of the linkers provided below in the section entitled “Linkers”. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via a linker that comprises between 1 and 200 amino acids. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via a linker that comprises from 1 to 5, 1 to 10, 1 to 20, 1 to 30, 1 to 40, 1 to 50, 1 to 60, 1 to 80, 1 to 100, 1 to 150, 1 to 200, 5 to 10, 5 to 20, 5 to 30, 5 to 40, 5 to 60, 5 to 80, 5 to 100, 5 to 150, 5 to 200, 10 to 20, 10 to 30, 10 to 40, 10 to 50, 10 to 60, 10 to 80, 10 to 100, 10 to 150, 10 to 200, 20 to 30, 20 to 40, 20 to 50, 20 to 60, 20 to 80, 20 to 100, 20 to 150, 20 to 200, 30 to 40, 30 to 50, 30 to 60, 30 to 80, 30 to 100, 30 to 150, 30 to 200, 40 to 50, 40 to 60, 40 to 80, 40 to 100, 40 to 150, 40 to 200, 50 to 60 50 to 80, 50 to 100, 50 to 150, 50 to 200, 60 to 80, 60 to 100, 60 to 150, 60 to 200, 80 to 100, 80 to 150, 80 to 200, 100 to 150, 100 to 200, or 150 to 200 amino acids in length. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via a linker that comprises 4, 16, 24, 32, 91 or 104 amino acids in length. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via a linker that comprises the amino acid sequence of SGSETPGTSESATPES (SEQ ID NO: 102), SGGS (SEQ ID NO: 103), SGGSSGSETPGTSESATPESSGGS (SEQ ID NO: 107), SGGSSGGSSGSETPGTSESATPESSGGSSGGS (SEQ ID NO: 108), GGSGGSPGSPAGSPTSTEEGTSESATPESGPGTSTEPSEGSAPGSPAGSPTSTEEGTSTE PSEGSAPGTSTEPSEGSAPGTSESATPESGPGSEPATSGGSGGS (SEQ ID NO: 109), or SGGSGGSGGS (SEQ ID NO: 120). In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the UBP, and/or the napDNAbp and the UBP are fused via a linker comprising the amino acid sequence SGSETPGTSESATPES (SEQ ID NO: 102), which may also be referred to as the XTEN linker.

Fusion Proteins Comprising a Nuclease Programmable DNA Binding Protein (napDNAbp), a Cytidine Deaminase, and a Nucleic Acid Polymerase (NAP) Domain

Some aspects of the disclosure provide fusion proteins comprising a nucleic acid programmable DNA binding protein (napDNAbp), a cytidine deaminase, and a nucleic acid polymerase (NAP) domain. In some embodiments, any of the fusion proteins provided herein are base editors. In some embodiments, the NAP is a eukaryotic nucleic acid polymerase. In some embodiments, the NAP is a DNA polymerase. In some embodiments, the NAP has translesion polymerase activity. In some embodiments, the NAP is a translesion DNA polymerase. In some embodiments, the NAP is a Rev7, Rev1 complex, polymerase iota, polymerase kappa, or polymerase eta. In some embodiments, the NAP is a eukaryotic polymerase alpha, beta, gamma, delta, epsilon, gamma, eta, iota, kappa, lambda, mu, or nu. In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a nucleic acid polymerase (e.g., a translesion DNA polymerase). In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the nucleic acid polymerases provided herein. For example, the NAP may comprise an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 54-64. In some embodiments, the NAP comprises the amino acid sequence of any one of SEQ ID NOs: 54-64.

In some embodiments, the napDNAbp is a Cas9 domain, a Cpf1 domain, a CasX domain, a CasY domain, a C2c1 domain, a C2c2 domain, aC2c3 domain, or an Argonaute domain. In some embodiments, the napDNAbp is any napDNAbp provided herein. In some embodiments, the napDNAbp of any of the fusion proteins provided herein is a Cas9 domain. The Cas9 domain may be any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein. In some embodiments, any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein may be fused with any of the cytidine deaminases provided herein. In some embodiments, the fusion protein comprises the structure:

-   -   NH₂-[cytidine deaminase]-[napDNAbp]-[NAP]-COOH;     -   NH₂-[cytidine deaminase]-[NAP]-[napDNAbp]-COOH;     -   NH₂-[NAP]-[cytidine deaminase]-[napDNAbp]-COOH;     -   NH₂-[NAP]-[napDNAbp]-[cytidine deaminase]-COOH;     -   NH₂-[napDNAbp]-[NAP]-[cytidine deaminase]-COOH; or     -   NH₂-[napDNAbp]-[cytidine deaminase]-[NAP]-COOH

In some embodiments, the fusion proteins comprising a cytidine deaminase, a napDNAbp (e.g., Cas9 domain), and NAP do not include a linker sequence. In some embodiments, a linker is present between the cytidine deaminase domain and the napDNAbp. In some embodiments, a linker is present between the cytidine deaminase domain and the NAP. In some embodiments, a linker is present between the napDNAbp and the NAP. In some embodiments, the “-” used in the general architecture above indicates the presence of an optional linker. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via any of the linkers provided herein. For example, in some embodiments the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via any of the linkers provided below in the section entitled “Linkers”. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via a linker that comprises between 1 and 200 amino acids. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via a linker that comprises from 1 to 5, 1 to 10, 1 to 20, 1 to 30, 1 to 40, 1 to 50, 1 to 60, 1 to 80, 1 to 100, 1 to 150, 1 to 200, 5 to 10, 5 to 20, 5 to 30, 5 to 40, 5 to 60, 5 to 80, 5 to 100, 5 to 150, 5 to 200, 10 to 20, 10 to 30, 10 to 40, 10 to 50, 10 to 60, 10 to 80, 10 to 100, 10 to 150, 10 to 200, 20 to 30, 20 to 40, 20 to 50, 20 to 60, 20 to 80, 20 to 100, 20 to 150, 20 to 200, 30 to 40, 30 to 50, 30 to 60, 30 to 80, 30 to 100, 30 to 150, 30 to 200, 40 to 50, 40 to 60, 40 to 80, 40 to 100, 40 to 150, 40 to 200, 50 to 60 50 to 80, 50 to 100, 50 to 150, 50 to 200, 60 to 80, 60 to 100, 60 to 150, 60 to 200, 80 to 100, 80 to 150, 80 to 200, 100 to 150, 100 to 200, or 150 to 200 amino acids in length. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via a linker that comprises 4, 16, 32, or 104 amino acids in length. In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via a linker that comprises the amino acid sequence of SGSETPGTSESATPES (SEQ ID NO: 102), SGGS (SEQ ID NO: 103), SGGSSGSETPGTSESATPESSGGS (SEQ ID NO: 107), SGGSSGGSSGSETPGTSESATPESSGGSSGGS (SEQ ID NO: 108), GGSGGSPGSPAGSPTSTEEGTSESATPESGPGTSTEPSEGSAPGSPAGSPTSTEEGTSTE PSEGSAPGTSTEPSEGSAPGTSESATPESGPGSEPATSGGSGGS (SEQ ID NO: 109), or SGGSGGSGGS (SEQ ID NO: 120). In some embodiments, the cytidine deaminase and the napDNAbp, the cytidine deaminase and the NAP, and/or the napDNAbp and the NAP are fused via a linker comprising the amino acid sequence SGSETPGTSESATPES (SEQ ID NO: 102), which may also be referred to as the XTEN linker.

Fusion Proteins Comprising a Nuclease Programmable DNA Binding Protein (napDNAbp), a Cytidine Deaminase, a Uracil Binding Protein (UBP), and a Nucleic Acid Polymerase (NAP) Domain

Some aspects of the disclosure provide fusion proteins comprising a nucleic acid programmable DNA binding protein (napDNAbp), a cytidine deaminase, a uracil binding protein (UBP), and a nucleic acid polymerase (NAP) domain. In some embodiments, any of the fusion proteins provided herein are base editors. In some embodiments, the NAP is a eukaryotic nucleic acid polymerase. In some embodiments, the NAP is a DNA polymerase. In some embodiments, the NAP has translesion polymerase activity. In some embodiments, the NAP is a translesion DNA polymerase. In some embodiments, the NAP is a Rev7, Rev1 complex, polymerase iota, polymerase kappa, or polymerase eta. In some embodiments, the NAP is a eukaryotic polymerase alpha, beta, gamma, delta, epsilon, gamma, eta, iota, kappa, lambda, mu, or nu. In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a nucleic acid polymerase (e.g., a translesion DNA polymerase). In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the nucleic acid polymerases provided herein. For example, the NAP may comprise an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 54-64. In some embodiments, the NAP comprises the amino acid sequence of any one of SEQ ID NOs: 54-64.

In some embodiments, the UBP is a uracil modifying enzyme. In some embodiments, the UBP is a uracil base excision enzyme. In some embodiments, the UBP is a uracil DNA glycosylase. In some embodiments, the UBP is any of the uracil binding proteins provided herein. For example, the UBP may be a UDG, a UdgX, a UdgX*, a UdgX_On, or a SMUG1. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a uracil binding protein, a uracil base excision enzyme or a uracil DNA glycosylase (UDG) enzyme. In some embodiments, the UBP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the uracil binding proteins provided herein. For example, the UBP may comprise an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 48-53. In some embodiments, the UBP comprises the amino acid sequence of any one of SEQ ID NOs: 48-53.

In some embodiments, the napDNAbp is a Cas9 domain, a Cpf1 domain, a CasX domain, a CasY domain, a C2c1 domain, a C2c2 domain, aC2c3 domain, or an Argonaute domain. In some embodiments, the napDNAbp is any napDNAbp provided herein. In some embodiments, the napDNAbp of any of the fusion proteins provided herein is a Cas9 domain. The Cas9 domain may be any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein. In some embodiments, any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein may be fused with any of the cytidine deaminases provided herein. In some embodiments, the fusion protein comprises the structure:

-   -   NH₂-[NAP]-[cytidine deaminase]-[napDNAbp]-[UBP]-COOH;     -   NH₂-[cytidine deaminase]-[NAP]-[napDNAbp]-[UBP]-COOH;     -   NH₂-[cytidine deaminase]-[napDNAbp]-[NAP]-[UBP]-COOH;     -   NH₂-[cytidine deaminase]-[napDNAbp]-[UBP]-[NAP]-COOH;     -   NH₂-[NAP]-[cytidine deaminase]-[UBP]-[napDNAbp]-COOH;     -   NH₂-[cytidine deaminase]-[NAP]-[UBP]-[napDNAbp]-COOH;     -   NH₂-[cytidine deaminase]-[UBP]-[NAP]-[napDNAbp]-COOH;     -   NH₂-[cytidine deaminase]-[UBP]-[napDNAbp]-[NAP]-COOH;     -   NH₂-[NAP]-[UBP]-[cytidine deaminase]-[napDNAbp]-COOH;     -   NH₂-[UBP]-[NAP]-[cytidine deaminase]-[napDNAbp]-COOH;     -   NH₂-[UBP]-[cytidine deaminase]-[NAP]-[napDNAbp]-COOH;     -   NH₂-[UBP]-[cytidine deaminase]-[napDNAbp]-[NAP]-COOH;     -   NH₂-[NAP]-[UBP]-[napDNAbp]-[cytidine deaminase]-COOH;     -   NH₂-[UBP]-[NAP]-[napDNAbp]-[cytidine deaminase]-COOH;     -   NH₂-[UBP]-[napDNAbp]-[NAP]-[cytidine deaminase]-COOH;     -   NH₂-[UBP]-[napDNAbp]-[cytidine deaminase]-[NAP]-COOH;     -   NH₂-[NAP]-[napDNAbp]-[UBP]-[cytidine deaminase]-COOH;     -   NH₂-[napDNAbp]-[NAP]-[UBP]-[cytidine deaminase]-COOH;     -   NH₂-[napDNAbp]-[UBP]-[NAP]-[cytidine deaminase]-COOH;     -   NH₂-[napDNAbp]-[UBP]-[cytidine deaminase]-[NAP]-COOH;     -   NH₂-[NAP]-[napDNAbp]-[cytidine deaminase]-[UBP]-COOH;     -   NH₂-[napDNAbp]-[NAP]-[cytidine deaminase]-[UBP]-COOH;     -   NH₂-[napDNAbp]-[cytidine deaminase]-[NAP]-[UBP]-COOH; or     -   NH₂-[napDNAbp]-[cytidine deaminase]-[UBP]-[NAP]-COOH

In some embodiments, the fusion proteins comprising a cytidine deaminase, a napDNAbp (e.g., Cas9 domain), a UBP, and NAP do not include a linker sequence. In some embodiments, a linker is present between the cytidine deaminase domain and the napDNAbp, the NAP, and/or the UBP. In some embodiments, a linker is present between the napDNAbp and the cytidine deaminase domain, the NAP, and/or the UBP. In some embodiments, a linker is present between the NAP and the cytidine deaminase, the napDNAbp and/or the UBP. In some embodiments, a linker is present between the UBP and the cytidine deaminase, the napDNAbp, and the NAP. In some embodiments, the “-” used in the general architecture above indicates the presence of an optional linker. In some embodiments, the linker is any of the linkers provided herein, for example, in the section entitled “Linkers”. In some embodiments, the linker comprises between 1 and 200 amino acids. In some embodiments, the linker comprises from 1 to 5, 1 to 10, 1 to 20, 1 to 30, 1 to 40, 1 to 50, 1 to 60, 1 to 80, 1 to 100, 1 to 150, 1 to 200, 5 to 10, 5 to 20, 5 to 30, 5 to 40, 5 to 60, 5 to 80, 5 to 100, 5 to 150, 5 to 200, 10 to 20, 10 to 30, 10 to 40, 10 to 50, 10 to 60, 10 to 80, 10 to 100, 10 to 150, 10 to 200, 20 to 30, 20 to 40, 20 to 50, 20 to 60, 20 to 80, 20 to 100, 20 to 150, 20 to 200, 30 to 40, 30 to 50, 30 to 60, 30 to 80, 30 to 100, 30 to 150, 30 to 200, 40 to 50, 40 to 60, 40 to 80, 40 to 100, 40 to 150, 40 to 200, 50 to 60 50 to 80, 50 to 100, 50 to 150, 50 to 200, 60 to 80, 60 to 100, 60 to 150, 60 to 200, 80 to 100, 80 to 150, 80 to 200, 100 to 150, 100 to 200, or 150 to 200 amino acids in length. In some embodiments, linker that comprises 4, 16, 32, or 104 amino acids in length. In some embodiments, the linker that comprises the amino acid sequence of SGSETPGTSESATPES (SEQ ID NO: 102), SGGS (SEQ ID NO: 103), SGGSSGSETPGTSESATPESSGGS (SEQ ID NO: 107), SGGSSGGSSGSETPGTSESATPESSGGSSGGS (SEQ ID NO: 108), GGSGGSPGSPAGSPTSTEEGTSESATPESGPGTSTEPSEGSAPGSPAGSPTSTEEGTSTE PSEGSAPGTSTEPSEGSAPGTSESATPESGPGSEPATSGGSGGS (SEQ ID NO: 109), or SGGSGGSGGS (SEQ ID NO: 120). In some embodiments, the linker comprises the amino acid sequence SGSETPGTSESATPES (SEQ ID NO: 102), which may also be referred to as the XTEN linker.

Fusion Proteins Comprising a Nuclease Programmable DNA Binding Protein (napDNAbp), and a Base Excision Enzyme (BEE)

Some aspects of the disclosure provide fusion proteins comprising a nucleic acid programmable DNA binding protein (napDNAbp), and a base excision enzyme. In some embodiments, any of the fusion proteins provided herein are base editors. In some embodiments, the base excision enzyme (BEE) is a cytosine, thymine, adenine, guanine, or uracil base excision enzyme. In some embodiments, the base excision enzyme (BEE) is a cytosine base excision enzyme. In some embodiments, the BEE is a thymine base excision enzyme. In some embodiments, the base excision enzyme comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a naturally-occurring BEE. In some embodiments, the base excision enzyme comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical any one of SEQ ID NOs: 65-66. In some embodiments, the base excision enzyme comprises the amino acid sequence of any one of SEQ ID NOs: 65-66.

In some embodiments, the napDNAbp is a Cas9 domain, a Cpf1 domain, a CasX domain, a CasY domain, a C2c1 domain, a C2c2 domain, aC2c3 domain, or an Argonaute domain. In some embodiments, the napDNAbp is any napDNAbp provided herein. In some embodiments, the napDNAbp of any of the fusion proteins provided herein is a Cas9 domain. The Cas9 domain may be any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein. In some embodiments, any of the Cas9 domains or Cas9 proteins (e.g., dCas9 or nCas9) provided herein may be fused with any of the cytidine deaminases provided herein. In some embodiments, the fusion protein comprises the structure:

-   -   NH₂-[BEE]-[napDNAbp]-COOH; or     -   NH₂-[napDNAbp]-[BEE]-COOH;

In some embodiments, the fusion protein further comprises a nucleic acid polymerase (NAP). In some embodiments, the NAP is a eukaryotic nucleic acid polymerase. In some embodiments, the NAP is a DNA polymerase. In some embodiments, the NAP has translesion polymerase activity. In some embodiments, the NAP is a translesion DNA polymerase. In some embodiments, the NAP is a Rev7, Rev1 complex, polymerase iota, polymerase kappa, or polymerase eta. In some embodiments, the NAP is a eukaryotic polymerase alpha, beta, gamma, delta, epsilon, gamma, eta, iota, kappa, lambda, mu, or nu. In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to a nucleic acid polymerase (e.g., a translesion DNA polymerase). In some embodiments, the NAP comprises an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any of the nucleic acid polymerases provided herein. For example, the NAP may comprise an amino acid sequence that is at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.5% identical to any one of SEQ ID NOs: 54-64. In some embodiments, the NAP comprises the amino acid sequence of any one of SEQ ID NOs: 54-64. In some embodiments, the fusion protein comprises the structure:

-   -   NH₂-[BEE]-[napDNAbp]-[NAP]-COOH;     -   NH₂-[BEE]-[NAP]-[napDNAbp]-COOH;     -   NH₂-[NAP]-[BEE]-[napDNAbp]-COOH;     -   NH₂-[NAP]-[napDNAbp]-[BEE]-COOH;     -   NH₂-[napDNAbp]-[NAP]-[BEE]-COOH; or     -   NH₂-[napDNAbp]-[BEE]-[NAP]-COOH

In some embodiments, the fusion proteins comprising a napDNAbp (e.g., Cas9 domain), and a BEE do not include a linker sequence. In some embodiments, the fusion proteins comprising a napDNAbp (e.g., Cas9 domain), a BEE, and a NAP do not include a linker sequence. In some embodiments, a linker is present between the napDNAbp and the BEE. In some embodiments, a linker is present between the BEE and the NAP and/or the napDNAbp. In some embodiments, a linker is present between the NAP and the BEE and/or the napDNAbp. In some embodiments, a linker is present between the napDNAbp and the BEE, and/or the NAP. In some embodiments, the “-” used in the general architecture above indicates the presence of an optional linker. In some embodiments, the linker is any of the linkers provided herein, for example, in the section entitled “Linkers”. In some embodiments, the linker comprises between 1 and 200 amino acids. In some embodiments, the linker comprises from 1 to 5, 1 to 10, 1 to 20, 1 to 30, 1 to 40, 1 to 50, 1 to 60, 1 to 80, 1 to 100, 1 to 150, 1 to 200, 5 to 10, 5 to 20, 5 to 30, 5 to 40, 5 to 60, 5 to 80, 5 to 100, 5 to 150, 5 to 200, 10 to 20, 10 to 30, 10 to 40, 10 to 50, 10 to 60, 10 to 80, 10 to 100, 10 to 150, 10 to 200, 20 to 30, 20 to 40, 20 to 50, 20 to 60, 20 to 80, 20 to 100, 20 to 150, 20 to 200, 30 to 40, 30 to 50, 30 to 60, 30 to 80, 30 to 100, 30 to 150, 30 to 200, 40 to 50, 40 to 60, 40 to 80, 40 to 100, 40 to 150, 40 to 200, 50 to 60 50 to 80, 50 to 100, 50 to 150, 50 to 200, 60 to 80, 60 to 100, 60 to 150, 60 to 200, 80 to 100, 80 to 150, 80 to 200, 100 to 150, 100 to 200, or 150 to 200 amino acids in length. In some embodiments, linker that comprises 4, 16, 32, or 104 amino acids in length. In some embodiments, the linker that comprises the amino acid sequence of SGSETPGTSESATPES (SEQ ID NO: 102), SGGS (SEQ ID NO: 103), SGGSSGSETPGTSESATPESSGGS (SEQ ID NO: 107), SGGSSGGSSGSETPGTSESATPESSGGSSGGS (SEQ ID NO: 108), GGSGGSPGSPAGSPTSTEEGTSESATPESGPGTSTEPSEGSAPGSPAGSPTSTEEGTSTE PSEGSAPGTSTEPSEGSAPGTSESATPESGPGSEPATSGGSGGS (SEQ ID NO: 109), or SGGSGGSGGS (SEQ ID NO: 120). In some embodiments, the linker comprises the amino acid sequence SGSETPGTSESATPES (SEQ ID NO: 102), which may also be referred to as the XTEN linker.

Fusion Proteins Comprising a Nuclear Localization Sequence (NLS)

In some embodiments, any of the fusion proteins provided herein further comprise one or more nuclear targeting sequences, for example, a nuclear localization sequence (NLS). In some embodiments, a NLS comprises an amino acid sequence that facilitates the importation of a protein, that comprises an NLS, into the cell nucleus (e.g., by nuclear transport). In some embodiments, any of the fusion proteins provided herein further comprise a nuclear localization sequence (NLS). In some embodiments, the NLS is fused to the N-terminus of the fusion protein. In some embodiments, the NLS is fused to the C-terminus of the fusion protein. In some embodiments, the NLS is fused to the N-terminus of the napDNAbp. In some embodiments, the NLS is fused to the C-terminus of the napDNAbp. In some embodiments, the NLS is fused to the N-terminus of the NAP. In some embodiments, the NLS is fused to the C-terminus of the NAP. In some embodiments, the NLS is fused to the N-terminus of the cytidine deaminase. In some embodiments, the NLS is fused to the C-terminus of the cytidine deaminase. In some embodiments, the NLS is fused to the N-terminus of the UBP. In some embodiments, the NLS is fused to the C-terminus of the UBP. In some embodiments, the NLS is fused to the N-terminus of the BEE. In some embodiments, the NLS is fused to the C-terminus of the BEE. In some embodiments, the NLS is fused to the fusion protein via one or more linkers. In some embodiments, the NLS is fused to the fusion protein without a linker. In some embodiments, the NLS comprises an amino acid sequence of any one of the NLS sequences provided or referenced herein. In some embodiments, the NLS comprises an amino acid sequence as set forth in SEQ ID NO: 41 or SEQ ID NO: 42. Additional nuclear localization sequences are known in the art and would be apparent to the skilled artisan. For example, NLS sequences are described in Plank et al., PCT/EP2000/011690, the contents of which are incorporated herein by reference for their disclosure of exemplary nuclear localization sequences. In some embodiments, a NLS comprises the amino acid sequence PKKKRKV (SEQ ID NO: 41), MDSLLMNRRKFLYQFKNVRWAKGRRETYLC (SEQ ID NO: 42), KRTADGSEFESPKKKRKV (SEQ ID NO: 43), KRGINDRNFWRGENGRKTR (SEQ ID NO: 44), KKTGGPIYRRVDGKWRR (SEQ ID NO: 45), RRELILYDKEEIRRIWR (SEQ ID NO: 46), or AVSRKRKA (SEQ ID NO: 47).

Linkers

A In certain embodiments, linkers may be used to link any of the proteins or protein domains described herein. The linker may be as simple as a covalent bond, or it may be a polymeric linker many atoms in length. In certain embodiments, the linker is a polypeptide or based on amino acids. In other embodiments, the linker is not peptide-like. In certain embodiments, the linker is a covalent bond (e.g., a carbon-carbon bond, disulfide bond, carbon-heteroatom bond, etc.). In certain embodiments, the linker is a carbon-nitrogen bond of an amide linkage. In certain embodiments, the linker is a cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic or heteroaliphatic linker. In certain embodiments, the linker is polymeric (e.g., polyethylene, polyethylene glycol, polyamide, polyester, etc.). In certain embodiments, the linker comprises a monomer, dimer, or polymer of aminoalkanoic acid. In certain embodiments, the linker comprises an aminoalkanoic acid (e.g., glycine, ethanoic acid, alanine, beta-alanine, 3-aminopropanoic acid, 4-aminobutanoic acid, 5-pentanoic acid, etc.). In certain embodiments, the linker comprises a monomer, dimer, or polymer of aminohexanoic acid (Ahx). In certain embodiments, the linker is based on a carbocyclic moiety (e.g., cyclopentane, cyclohexane). In other embodiments, the linker comprises a polyethylene glycol moiety (PEG). In other embodiments, the linker comprises amino acids. In certain embodiments, the linker comprises a peptide. In certain embodiments, the linker comprises an aryl or heteroaryl moiety. In certain embodiments, the linker is based on a phenyl ring. The linker may include functionalized moieties to facilitate attachment of a nucleophile (e.g., thiol, amino) from the peptide to the linker. Any electrophile may be used as part of the linker. Exemplary electrophiles include, but are not limited to, activated esters, activated amides, Michael acceptors, alkyl halides, aryl halides, acyl halides, and isothiocyanates.

In some embodiments, the linker is an amino acid or a plurality of amino acids (e.g., a peptide or protein). In some embodiments, the linker is a bond (e.g., a covalent bond), an organic molecule, group, polymer, or chemical moiety. In some embodiments, the linker is 5-100 amino acids in length, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 30-35, 35-40, 40-45, 45-50, 50-60, 60-70, 70-80, 80-90, 90-100, 100-110, 110-120, 120-130, 130-140, 140-150, or 150-200 amino acids in length. Longer or shorter linkers are also contemplated. In some embodiments, a linker comprises the amino acid sequence SGSETPGTSESATPES (SEQ ID NO: 102), which may also be referred to as the XTEN linker. In some embodiments, a linker comprises the amino acid sequence SGGS (SEQ ID NO: 103). In some embodiments, a linker comprises (SGGS)_(n) (SEQ ID NO: 103), (GGGS)n (SEQ ID NO: 104), (GGGGS)n (SEQ ID NO: 105), (G)n (SEQ ID NO: 121), (EAAAK)n (SEQ ID NO: 106), (GGS)n (SEQ ID NO: 122), SGSETPGTSESATPES (SEQ ID NO: 102), SGGSGGSGGS (SEQ ID NO: 120), or (XP)_(n) motif (SEQ ID NO: 123), or a combination of any of these, wherein n is independently an integer between 1 and 30, and wherein X is any amino acid. In some embodiments, n is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. In some embodiments, a linker comprises SGSETPGTSESATPES (SEQ ID NO: 102), and SGGS (SEQ ID NO: 103). In some embodiments, a linker comprises SGGSSGSETPGTSESATPESSGGS (SEQ ID NO: 107). In some embodiments, a linker comprises SGGSSGGSSGSETPGTSESATPESSGGSSGGS (SEQ ID NO: 108). In some embodiments, a linker comprises GGSGGSPGSPAGSPTSTEEGTSESATPESGPGTSTEPSEGSAPGSPAGSPTSTEEGTSTE PSEGSAPGTSTEPSEGSAPGTSESATPESGPGSEPATSGGSGGS (SEQ ID NO: 109). In some embodiments, a linker comprises SGGSGGSGGS (SEQ ID NO: 120).

Nucleic Acid Programmable DNA Binding Protein (napDNAbp) Complexes with Guide Nucleic Acids

Some aspects of this disclosure provide complexes comprising any of the fusion proteins provided herein, and a guide nucleic acid bound to napDNAbp of the fusion protein. Some aspects of this disclosure provide complexes comprising any of the fusion proteins provided herein, and a guide RNA bound to a Cas9 domain (e.g., a dCas9, a nuclease active Cas9, or a Cas9 nickase) of fusion protein.

In some embodiments, the guide nucleic acid (e.g., guide RNA) is from 15-100 nucleotides long and comprises a sequence of at least 10 contiguous nucleotides that is complementary to a target sequence. In some embodiments, the guide RNA is 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 nucleotides long. In some embodiments, the guide RNA comprises a sequence of 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40 contiguous nucleotides that is complementary to a target sequence. In some embodiments, the target sequence is a DNA sequence. In some embodiments, the target sequence is an RNA sequence. In some embodiments, the target sequence is a sequence in the genome of a mammal. In some embodiments, the target sequence is a sequence in the genome of a human. In some embodiments, the 3′ end of the target sequence is immediately adjacent to a canonical PAM sequence (NGG). In some embodiments, the guide nucleic acid (e.g., guide RNA) is complementary to a sequence associated with a disease or disorder. In some embodiments, the guide nucleic acid (e.g., guide RNA) is complementary to a sequence associated with a disease or disorder having a mutation in a gene associated with any of the diseases or disorders provided herein. In some embodiments, the guide nucleic acid (e.g., guide RNA) is complementary to any of the genes associated with a disease or disorder as provided herein.

Methods of Using Fusion Proteins

Some aspects of this disclosure provide methods of using any of the fusion proteins (e.g., base editors) provided herein, or complexes comprising a guide nucleic acid (e.g., gRNA) and a fusion protein (e.g., base editor) provided herein. For example, some aspects of this disclosure provide methods comprising contacting a DNA, or RNA molecule with any of the fusion proteins or base editors provided herein, and with at least one guide nucleic acid (e.g., guide RNA), wherein the guide nucleic acid, (e.g., guide RNA) is about 15-100 nucleotides long and comprises a sequence of at least 10 contiguous nucleotides that is complementary to a target sequence. In some embodiments, the 3′ end of the target sequence is immediately adjacent to a canonical spCas9 PAM sequence (NGG). In some embodiments, the 3′ end of the target sequence is not immediately adjacent to a spCas9 canonical PAM sequence (NGG). In some embodiments, the 3′ end of the target sequence is immediately adjacent to an AGC, GAG, TTT, GTG, or CAA sequence.

In some embodiments, the target DNA sequence comprises a sequence associated with a disease or disorder. In some embodiments, the target DNA sequence comprises a point mutation associated with a disease or disorder. In some embodiments, the activity of the fusion protein (e.g., comprising a napDNAbp, a cytidine deaminase, and a uracil binding protein UBP), or the complex, results in a correction of the point mutation. In some embodiments, the target DNA sequence comprises a G to C, or C to G point mutation associated with a disease or disorder, and wherein deamination and/or excision of a mutant C base results in a sequence that is not associated with a disease or disorder. In some embodiments, the target DNA sequence encodes a protein, and the point mutation is in a codon and results in a change in the amino acid encoded by the mutant codon as compared to the wild-type codon. In some embodiments, the deamination of the mutant C results in a change of the amino acid encoded by the mutant codon. In some embodiments, the deamination of the mutant C results in the codon encoding the wild-type amino acid. In some embodiments, the contacting is in vivo in a subject. In some embodiments, the subject has or has been diagnosed with a disease or disorder. In some embodiments, the disease or disorder is 22q13.3 deletion syndrome; 2-methyl-3-hydroxybutyric aciduria; 3 Methylcrotonyl-CoA carboxylase 1 deficiency; 3-methylcrotonyl CoA carboxylase 2 deficiency; 3-Methylglutaconic aciduria type 2; 3-Methylglutaconic aciduria type 3; 3-methylglutaconic aciduria type V; 3-Oxo-5 alpha-steroid delta 4-dehydrogenase deficiency; 46,XY sex reversal, type 1; 46,XY true hermaphroditism, SRY-related; 4-Hydroxyphenylpyruvate dioxygenase deficiency; Abnormal facial shape; Abnormal glycosylation (CDG IIa); Achondrogenesis type 2; Achromatopsia 2; Achromatopsia 5; Achromatopsia 6; Achromatopsia 7; Acquired hemoglobin H disease; Acrocephalosyndactyly type I; Acrodysostosis 1 with or without hormone resistance; Acrodysostosis 2, with or without hormone resistance; Acrofacial Dysostosis, Cincinnati type; ACTH resistance; Acute neuronopathic Gaucher disease; Adams-Oliver syndrome; Adams-Oliver syndrome 2; Adams-Oliver syndrome 4; Adams-Oliver Syndrome 6; Adenine phosphoribosyltransferase deficiency; Adenylosuccinate lyase deficiency; Adolescent nephronophthisis; Adrenoleukodystrophy; Adult junctional epidermolysis bullosa; Adult neuronal ceroid lipofuscinosis; ADULT syndrome; Age-related macular degeneration 14; Age-related macular degeneration 3; Aicardi Goutieres syndrome 5; Aicardi-goutieres syndrome 6; Alexander disease; alpha Thalassemia; Alpha-B crystallinopathy; Alport syndrome, autosomal recessive; Alport syndrome, X-linked recessive; Alternating hemiplegia of childhood 2; Alzheimer disease; Alzheimer disease, type 1; Alzheimer disease, type 3; Amelogenesis Imperfecta, Hypomaturation type, IIA3; Amelogenesis imperfecta, type 1E; Amish lethal microcephaly; AML—Acute myeloid leukemia; Amyloidogenic transthyretin amyloidosis; Amyotrophic lateral sclerosis 16, juvenile; Amyotrophic lateral sclerosis 6, autosomal recessive; Amyotrophic lateral sclerosis type 1; Amyotrophic lateral sclerosis type 10; Amyotrophic lateral sclerosis type 2; Amyotrophic lateral sclerosis type 9; Andersen Tawil syndrome; Anemia, Dyserythropoietic Congenital, Type IV; Anemia, nonspherocytic hemolytic, due to G6PD deficiency; Anemia, sideroblastic, pyridoxine-refractory, autosomal recessive; Angelman syndrome; Angiopathy, hereditary, with nephropathy, aneurysms, and muscle cramps; Anhidrotic ectodermal dysplasia with immune deficiency; Anonychia; Antley-Bixler syndrome with genital anomalies and disordered steroidogenesis; Antley-Bixler syndrome without genital anomalies or disordered steroidogenesis; Aplastic anemia; Apolipoprotein a-i deficiency; Arginase deficiency; Arrhythmogenic right ventricular cardiomyopathy; Arrhythmogenic right ventricular cardiomyopathy, type 11; Arrhythmogenic right ventricular cardiomyopathy, type 9; Arterial calcification of infancy; Arterial tortuosity syndrome; Arthrogryposis multiplex congenita distal type 1; Arthrogryposis renal dysfunction cholestasis syndrome; Arthrogryposis, distal, type 5d; Arts syndrome; Aspartylglucosaminuria, finnish type; Asphyxiating thoracic dystrophy 2; Ataxia with vitamin E deficiency; Ataxia-telangiectasia syndrome; Ataxia-telangiectasia-like disorder; Atelosteogenesis type 1; Atrial fibrillation; Atrial fibrillation, familial, 10; Atrial septal defect 4; Atrophia bulborum hereditaria; ATR-X syndrome; Atypical hemolytic-uremic syndrome 1; Auditory neuropathy, autosomal recessive, 1; Auriculocondylar syndrome 1; Autoimmune disease, multisystem, infantile-onset; Autoimmune lymphoproliferative syndrome, type 1A; Autoimmune Lymphoproliferative Syndrome, type V; Autosomal dominant nocturnal frontal lobe epilepsy; Autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions 2; Autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions 3; Autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions 4; Autosomal recessive congenital ichthyosis 1; Autosomal recessive congenital ichthyosis 5; Autosomal recessive hypophosphatemic vitamin D refractory rickets; Axenfeld-rieger anomaly; Axenfeld-Rieger syndrome type 1; Axenfeld-Rieger syndrome type 3; Baraitser-Winter syndrome 1; Bardet-Biedl syndrome; Bardet-Biedl syndrome 10; Bardet-Biedl syndrome 12; Bardet-Biedl syndrome 2; Bardet-Biedl syndrome 3; Bardet-Biedl syndrome 4; Bardet-Biedl syndrome 9; Bartter syndrome antenatal type 2; Bartter syndrome, type 4b; Basal ganglia disease, biotin-responsive; Becker muscular dystrophy; Benign familial neonatal seizures 1; Benign familial neonatal-infantile seizures; Benign recurrent intrahepatic cholestasis 2; Bernard-Soulier syndrome, type B; beta Thalassemia; Bietti crystalline corneoretinal dystrophy; Bile acid synthesis defect, congenital, 2; Biotinidase deficiency; Bleeding disorder, platelet-type, 19; Blood Group—Lutheran Inhibitor; Bloom syndrome; Bosley-Salih-Alorainy syndrome; Boucher Neuhauser syndrome; Brachydactyly type B2; Breast cancer; Breast-ovarian cancer, familial 1; Breast-ovarian cancer, familial 2; Bronchiectasis; Brown-Vialetto-Van laere syndrome; Brown-Vialetto-Van Laere syndrome 2; Bullous ichthyosiform erythroderma; Burkitt lymphoma; Camptomelic dysplasia; Cap myopathy 2; Carbohydrate-deficient glycoprotein syndrome type I; Carbohydrate-deficient glycoprotein syndrome type II; Carcinoma of colon; Carcinoma of pancreas; Cardiac arrhythmia; Cardioencephalomyopathy, Fatal Infantile, Due To Cytochrome C Oxidase Deficiency 3; Cardiofaciocutaneous syndrome; Cardiofaciocutaneous syndrome 2; Cardiomyopathy; Cardiomyopathy, restrictive; Carney complex, type 1; Carnitine palmitoyltransferase I deficiency; Cataract 1; Cataracts, congenital, with sensorineural deafness, down syndrome-like facial appearance, short stature, and mental retardation; Catecholaminergic polymorphic ventricular tachycardia; Central core disease; Central precocious puberty; Cerebellar ataxia and hypogonadotropic hypogonadism; Cerebellar ataxia infantile with progressive external ophthalmoplegia; Cerebellar ataxia, deafness, and narcolepsy; Cerebral amyloid angiopathy, APP-related; Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy; Cerebral cavernous malformations 1; Cerebral palsy, spastic quadriplegic, 1; Cerebro-costo-mandibular syndrome; Ceroid lipofuscinosis neuronal 1; Ceroid lipofuscinosis neuronal 10; Ceroid lipofuscinosis neuronal 6; Ceroid lipofuscinosis neuronal 7; Ceroid lipofuscinosis neuronal 8; Ceroid lipofuscinosis, neuronal, 13; Ceroid lipofuscinosis, neuronal, 2; Ch\xc3\xa9diak-Higashi syndrome; Char syndrome; Charcot-Marie-Tooth disease; Charcot-Marie-Tooth disease type 1B; Charcot-Marie-Tooth disease type 2B; Charcot-Marie-Tooth disease type 2D; Charcot-Marie-Tooth disease type 21; Charcot-Marie-Tooth disease type 2K; Charcot-Marie-Tooth disease, axonal, with vocal cord paresis, autosomal recessive; Charcot-Marie-Tooth Disease, demyelinating, Type 1C; Charcot-Marie-Tooth disease, dominant intermediate E; Charcot-Marie-Tooth disease, type 2; Charcot-Marie-Tooth disease, type 2A2; Charcot-Marie-Tooth disease, type 4C; Charcot-Marie-Tooth disease, type 4G; Charcot-Marie-Tooth disease, type IA; Charcot-Marie-Tooth disease, type IE; Charcot-Marie-Tooth disease, type IF; Charcot-Marie-Tooth disease, X-linked recessive, type 5; CHARGE association; Child syndrome; Cholestanol storage disease; Cholesterol monooxygenase (side-chain cleaving) deficiency; Chondrodysplasia punctata 1, X-linked recessive; Chops Syndrome; Chromosome 9q deletion syndrome; Chronic granulomatous disease, X-linked; Ciliary dyskinesia, primary, 14; Ciliary dyskinesia, primary, 19; Ciliary dyskinesia, primary, 3; Ciliary dyskinesia, primary, 7; Cleidocranial dysostosis; Cockayne syndrome type A; Coffin-Lowry syndrome; Cohen syndrome; Cole disease; Colorectal cancer, hereditary, nonpolyposis, type 1; Combined cellular and humoral immune defects with granulomas; Combined oxidative phosphorylation deficiency 24; Combined oxidative phosphorylation deficiency 9; Common variable immunodeficiency 7; Complement component 9 deficiency; Cone-rod dystrophy 10; Cone-rod dystrophy 11; Cone-rod dystrophy 3; Cone-rod dystrophy 5; Cone-rod dystrophy 6; Congenital adrenal hypoplasia, X-linked; Congenital amegakaryocytic thrombocytopenia; Congenital aniridia; Congenital bilateral absence of the vas deferens; Congenital cataracts, hearing loss, and neurodegeneration; Congenital contractural arachnodactyly; Congenital defect of folate absorption; Congenital disorder of glycosylation type 1K; Congenital disorder of glycosylation type 1M; Congenital disorder of glycosylation type 1t; Congenital disorder of glycosylation type 1u; Congenital disorder of glycosylation type 2C; Congenital generalized lipodystrophy type 1; Congenital generalized lipodystrophy type 2; Congenital heart defects, multiple types, 1, X-linked; Congenital lactase deficiency; Congenital long QT syndrome; Congenital muscular dystrophy-dystroglycanopathy with brain and eye anomalies, type A2; Congenital muscular dystrophy-dystroglycanopathy with brain and eye anomalies, type A7; Congenital muscular dystrophy-dystroglycanopathy with mental retardation, type B1; Congenital muscular dystrophy-dystroglycanopathy with mental retardation, type B2; Congenital myopathy with fiber type disproportion; Congenital myotonia, autosomal dominant form; Congenital myotonia, autosomal recessive form; Congenital stationary night blindness, autosomal dominant 3; Congenital stationary night blindness, type 1A; Congenital stationary night blindness, type 1F; Coproporphyria; Corneal dystrophy, Fuchs endothelial, 8; Corneal epithelial dystrophy; Corneal fragility keratoglobus, blue sclerae and joint hypermobility; Cornelia de Lange syndrome 1; Cornelia de Lange syndrome 4; Cortical dysplasia, complex, with other brain malformations 3; Cortisone reductase deficiency 1; Cowden syndrome 2; Cranioectodermal dysplasia 1; Craniofacial deafness hand syndrome; Cranioosteoarthropathy; Craniosynostosis; Craniosynostosis 3; Craniosynostosis and dental anomalies; Creatine deficiency, X-linked; Crigler Najjar syndrome, type 1; Crouzon syndrome; Cryptophthalmos syndrome; Cryptorchidism, unilateral or bilateral; Cushing symphalangism; Cutis Gyrata syndrome of Beare and Stevenson; Cystathioninuria; Cystic fibrosis; Cystinosis, ocular nonnephropathic; Cytochrome-c oxidase deficiency; Danon disease; Deafness, autosomal dominant 12; Deafness, autosomal dominant 20; Deafness, autosomal recessive 1A; Deafness, autosomal recessive 63; Deafness, autosomal recessive 8; Deafness, autosomal recessive 9; Deficiency of acetyl-CoA acetyltransferase; Deficiency of alpha-mannosidase; Deficiency of ferroxidase; Deficiency of glycerol kinase; Deficiency of guanidinoacetate methyltransferase; Deficiency of hydroxymethylglutaryl-CoA lyase; Deficiency of iodide peroxidase; Deficiency of malonyl-CoA decarboxylase; Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase; Delayed speech and language development; delta Thalassemia; Dent disease 1; Desbuquois syndrome; Desmosterolosis; DFNA 2 Nonsyndromic Hearing Loss; Diabetes mellitus type 2; Diabetes mellitus, insulin-dependent, 20; Digitorenocerebral syndrome; Dilated cardiomyopathy 1FF; Dilated cardiomyopathy 1G; Dilated cardiomyopathy 1S; Dilated cardiomyopathy 1X; Dilated cardiomyopathy 3B; Disordered steroidogenesis due to cytochrome p450 oxidoreductase deficiency; Distal hereditary motor neuronopathy type 2B; Distichiasis-lymphedema syndrome; Drash syndrome; Duchenne muscular dystrophy; Dyskeratosis congenita autosomal dominant; Dyskeratosis congenita X-linked; Dyskeratosis congenita, autosomal dominant, 2; Dyskeratosis congenita, autosomal recessive, 5; Dystonia 1; DYSTONIA 27; Dystonia 5, Dopa-responsive type; Dystonia, dopa-responsive, with or without hyperphenylalaninemia, autosomal recessive; Early infantile epileptic encephalopathy 13; Early infantile epileptic encephalopathy 2; Early infantile epileptic encephalopathy 8; Early infantile epileptic encephalopathy 9; Early myoclonic encephalopathy; Ectodermal dysplasia-syndactyly syndrome 1; Ectrodactyly, ectodermal dysplasia, and cleft lip/palate syndrome 3; Ehlers-Danlos syndrome, classic type; Ehlers-Danlos syndrome, hydroxylysine-deficient; Ehlers-Danlos syndrome, musculocontractural type; Ehlers-Danlos syndrome, type 4; Eichsfeld type congenital muscular dystrophy; Elliptocytosis 3; Endometrial carcinoma; Endplate acetylcholinesterase deficiency; Enlarged vestibular aqueduct syndrome; Enterokinase deficiency; Epidermolysis bullosa simplex, Koebner type; Epilepsy, nocturnal frontal lobe, type 3; Epilepsy, progressive myoclonic 1A (Unverricht and Lundborg); Epilepsy, progressive myoclonic 2b; Epileptic encephalopathy, early infantile, 1; Epileptic encephalopathy, early infantile, 24; Epileptic encephalopathy, early infantile, 28; Epileptic Encephalopathy, Early Infantile, 31; Epiphyseal chondrodysplasia, miura type; Episodic ataxia type 1; Episodic ataxia, type 6; Episodic pain syndrome, familial, 3; Erythrocytosis, familial, 2; Erythrocytosis, familial, 3; Erythrokeratodermia with ataxia; Exudative vitreoretinopathy 1; Exudative vitreoretinopathy 5; Fabry disease; Fabry disease, cardiac variant; Factor v and factor viii, combined deficiency of, 2; Familial amyloid nephropathy with urticaria AND deafness; Familial cancer of breast; Familial cold urticaria; Familial febrile seizures 8; Familial hemiplegic migraine type 3; Familial hypertrophic cardiomyopathy 1; Familial hypertrophic cardiomyopathy 10; Familial hypertrophic cardiomyopathy 11; Familial hypertrophic cardiomyopathy 20; Familial hypertrophic cardiomyopathy 23; Familial hypertrophic cardiomyopathy 4; Familial hypertrophic cardiomyopathy 6; Familial hypoplastic, glomerulocystic kidney; Familial infantile myasthenia; Familial juvenile gout; Familial Mediterranean fever; Familial platelet disorder with associated myeloid malignancy; Familial porencephaly; Familial porphyria cutanea tarda; Familial visceral amyloidosis, Ostertag type; Fanconi anemia, complementation group C; Fanconi anemia, complementation group F; Fanconi anemia, complementation group G; Fanconi anemia, complementation group J; Fanconi Anemia, complementation group T; Farber lipogranulomatosis; Fetal hemoglobin quantitative trait locus 1; Fetal hemoglobin quantitative trait locus 6; Fibrochondrogenesis; Focal epilepsy with speech disorder with or without mental retardation; Focal segmental glomerulosclerosis 6; Foveal hypoplasia and presenile cataract syndrome; Frontonasal dysplasia 1; Frontonasal dysplasia 2; Frontotemporal dementia; Fructose-biphosphatase deficiency; Fumarase deficiency; Galactosylceramide beta-galactosidase deficiency; Gallbladder disease 4; Gamstorp-Wohlfart syndrome; Ganglioside sialidase deficiency; Gangliosidosis GM1 type 3; Gardner syndrome; GATA-1-related thrombocytopenia with dyserythropoiesis; Gaucher disease; Gaucher disease type 3C; Gaucher disease, perinatal lethal; Gaucher disease, type 1; Generalized epilepsy with febrile seizures plus, type 1; Generalized epilepsy with febrile seizures plus, type 2; Generalized epilepsy with febrile seizures plus, type 9; Gerstmann-Straussler-Scheinker syndrome; Glanzmann thrombasthenia; Glaucoma 1, open angle, F; Glaucoma, congenital; Global developmental delay; Glucocorticoid deficiency 4; Glutaric aciduria, type 1; Glycogen storage disease Ma; Glycogen storage disease IV, congenital neuromuscular; Glycogen storage disease IXb; Glycogen storage disease of heart, lethal congenital; Glycogen storage disease, type II; Glycogen storage disease, type IV; Glycogen storage disease, type V; Glycogen storage disease, type VI; Glycosylphosphatidylinositol deficiency; Gray platelet syndrome; Griscelli syndrome type 2; Growth and mental retardation, mandibulofacial dysostosis, microcephaly, and cleft palate; Growth hormone insensitivity with immunodeficiency; Hemochromatosis type 1; Hemochromatosis type 3; Hemolytic anemia due to hexokinase deficiency; Hemolytic anemia, nonspherocytic, due to glucose phosphate isomerase deficiency; Hemosiderosis, systemic, due to aceruloplasminemia; Hennekam lymphangiectasia-lymphedema syndrome; Hereditary acrodermatitis enteropathica; Hereditary angioedema type 1; Hereditary breast and ovarian cancer syndrome; Hereditary cancer-predisposing syndrome; Hereditary diffuse gastric cancer; Hereditary diffuse leukoencephalopathy with spheroids; Hereditary factor II deficiency disease; Hereditary factor IX deficiency disease; Hereditary factor VIII deficiency disease; Hereditary factor XI deficiency disease; Hereditary fructosuria; Hereditary leiomyomatosis and renal cell cancer; Hereditary lymphedema type I; Hereditary neuralgic amyotrophy; Hereditary nonpolyposis colorectal cancer type 5; Hereditary Nonpolyposis Colorectal Neoplasms; Hereditary pancreatitis; Hereditary Paraganglioma-Pheochromocytoma Syndromes; Hereditary pyropoikilocytosis; Hereditary sensory neuropathy type 1D; Hereditary sideroblastic anemia; Heterotaxy, visceral, X-linked; Heterotopia; Hirschsprung disease ganglioneuroblastoma; Histiocytic medullary reticulosis; Holoprosencephaly 11; Holoprosencephaly 2; Holoprosencephaly 3; Holoprosencephaly 4; Homocysteinemia due to MTHFR deficiency; Homocystinuria due to CBS deficiency; Hurler syndrome; Hurthle cell carcinoma of thyroid; Hutchinson-Gilford syndrome; Hypercalciuria, childhood, self-limiting; Hypercholesterolaemia; Hyperekplexia 3; Hyperekplexia hereditary; Hyperferritinemia cataract syndrome; Hyperlipoproteinemia, type I; Hyperlipoproteinemia, type ID; Hyperlysinemia; Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome; Hyperproinsulinemia; Hypertelorism, severe, with midface prominence, myopia, mental retardation, and bone fragility; Hypertrophic cardiomyopathy; Hypocalcemia, autosomal dominant 1; Hypocalcemia, autosomal dominant 1, with bartter syndrome; Hypochondroplasia; Hypochromic microcytic anemia with iron overload; Hypoglycemia with deficiency of glycogen synthetase in the liver; Hypogonadotropic hypogonadism 13 with or without anosmia; Hypohidrotic X-linked ectodermal dysplasia; Hypokalemic periodic paralysis 1; Hypomagnesemia 1, intestinal; Hypomagnesemia 5, renal, with ocular involvement; Hypomagnesemia, seizures, and mental retardation; Hypomyelinating leukodystrophy 7; Hypomyelinating leukodystrophy 8, with or without oligodontia and/or hypogonadotropic hypogonadism; Hypoproteinemia, hypercatabolic; Hypothyroidism, congenital, nongoitrous, 1; Hypothyroidism, congenital, nongoitrous, 5; Hypothyroidism, congenital, nongoitrous, 6; Hypotrichosis 6; Hypotrichosis-lymphedema-telangiectasia syndrome; I cell disease; Ichthyosis vulgaris; Idiopathic basal ganglia calcification 5; Immunodeficiency 12; Immunodeficiency 23; Immunodeficiency 24; Immunodeficiency 30; Immunodeficiency 31a; Immunodeficiency 31C; Immunodeficiency with hyper IgM type 1; Inclusion body myopathy 2; Infantile cerebellar-retinal degeneration; Infantile GM1 gangliosidosis; Infantile hypophosphatasia; Infantile nystagmus, X-linked; Insulin-resistant diabetes mellitus AND acanthosis nigricans; Intellectual disability; Intermediate maple syrup urine disease type 2; Invasive pneumococcal disease, recurrent isolated, 2; Irido-corneo-trabecular dysgenesis; Iron accumulation in brain; Jackson-Weiss syndrome; Jakob-Creutzfeldt disease; Joubert syndrome 23; Juvenile GM>1<gangliosidosis; Juvenile polyposis syndrome; Kabuki make-up syndrome; Kallmann syndrome 3; Kallmann syndrome 4; Kallmann syndrome 5; Kallmann syndrome 6; Keratoconus 1; Kohlschutter syndrome; Kugelberg-Welander disease; Lafora disease; Langer mesomelic dysplasia syndrome; Laron-type isolated somatotropin defect; Larsen syndrome, dominant type; Lchad deficiency with maternal acute fatty liver of pregnancy; Leber congenital amaurosis 13; Leber congenital amaurosis 4; Leber congenital amaurosis 9; Leigh disease; LEOPARD syndrome; LEOPARD syndrome 1; LEOPARD syndrome 2; Leprechaunism syndrome; Leri Weill dyschondrosteosis; Lesch-Nyhan syndrome; Leukodystrophy, hypomyelinating, 6; Leukoencephalopathy with ataxia; Leukoencephalopathy with Brainstem and Spinal Cord Involvement and Lactate Elevation; Leukoencephalopathy with vanishing white matter; Leydig cell agenesis; Li-Fraumeni syndrome 1; Limb-girdle muscular dystrophy; Limb-girdle muscular dystrophy, type 1B; Limb-girdle muscular dystrophy, type 1C; Limb-girdle muscular dystrophy, type 1E; Limb-girdle muscular dystrophy, type 2A; Limb-girdle muscular dystrophy, type 2B; Limb-girdle muscular dystrophy, type 2E; Limb-girdle muscular dystrophy, type 2F; Limb-girdle muscular dystrophy, type 2L; Limb-girdle muscular dystrophy-dystroglycanopathy, type C1; Limb-girdle muscular dystrophy-dystroglycanopathy, type C14; Limb-girdle muscular dystrophy-dystroglycanopathy, type C2; Limb-girdle muscular dystrophy-dystroglycanopathy, type C7; Lissencephaly 1; Long QT syndrome 1; Long QT syndrome 13; Long QT syndrome 15; Long QT syndrome 2; Long QT syndrome 9; Long QT syndrome, LQT1 subtype; Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency; Lowe syndrome; Luteinizing hormone resistance, female; Lymphoproliferative syndrome 1; Lymphoproliferative syndrome 1, X-linked; Lynch syndrome I; Lynch syndrome II; Macrothrombocytopenia, familial, Bernard-Soulier type; Macular dystrophy with central cone involvement; Majeed syndrome; Malignant tumor of esophagus; Malignant tumor of prostate; Mandibuloacral dysostosis; Maple syrup urine disease; Maple syrup urine disease type 1A; Maple syrup urine disease type 2; Marfan syndrome; Marie Unna hereditary hypotrichosis 1; Maturity-onset diabetes of the young, type 2; Maturity-onset diabetes of the young, type 3; Medium-chain acyl-coenzyme A dehydrogenase deficiency; Meier-Gorlin syndrome 5; Melnick-Fraser syndrome; MEN2 phenotype: Unclassified; MEN2 phenotype: Unknown; Menkes kinky-hair syndrome; Menopause, natural, age at, quantitative trait locus 3; Mental retardation 30, X-linked; Mental retardation and microcephaly with pontine and cerebellar hypoplasia; Mental retardation, autosomal dominant 13; Mental retardation, autosomal dominant 16; Mental retardation, autosomal dominant 29; Mental Retardation, Autosomal Dominant 38; Mental retardation, autosomal dominant 7; Mental retardation, autosomal recessive 34; Mental Retardation, Autosomal Recessive 49; Mental retardation, stereotypic movements, epilepsy, and/or cerebral malformations; Mental retardation, syndromic, Claes-Jensen type, X-linked; Mental retardation, X-linked, syndromic 13; Mental retardation, X-linked, syndromic 32; Mental retardation, X-linked, syndromic, raymond type; Mental retardation, X-linked, syndromic, wu type; Mental retardation-hypotonic facies syndrome X-linked, 1; Merosin deficient congenital muscular dystrophy; Metachromatic leukodystrophy; Metaphyseal chondrodysplasia, Schmid type; Methylcobalamin Deficiency, cblg type; Methylmalonic Aciduria, mut(0) type; Microcephaly and chorioretinopathy, autosomal recessive, 2; Microcephaly with or without chorioretinopathy, lymphedema, or mental retardation; Microcytic anemia; Micropenis; Microphthalmia syndromic 3; Microphthalmia syndromic 5; Microphthalmia, isolated 3; Microphthalmia, isolated 6; Microphthalmia, isolated, with coloboma 7; Microvascular complications of diabetes 7; Mild non-PKU hyperphenylalanemia; Mitochondrial complex I deficiency; Mitochondrial complex II deficiency; Mitochondrial complex III deficiency; Mitochondrial DNA depletion syndrome 13 (encephalomyopathic type); Mitochondrial DNA depletion syndrome 2; Mitochondrial DNA depletion syndrome 9 (encephalomyopathic with methylmalonic aciduria); Mitochondrial Short-Chain Enoyl-CoA Hydratase 1 Deficiency; Mitochondrial trifunctional protein deficiency; Miyoshi muscular dystrophy 1; Miyoshi muscular dystrophy 3; Mohr-Tranebjaerg syndrome; Mosaic variegated aneuploidy syndrome; Mowat-Wilson syndrome; Mucolipidosis III Gamma; Mucopolysaccharidosis type VI; Mucopolysaccharidosis, MPS-II; Mucopolysaccharidosis, MPS-III-B; Mucopolysaccharidosis, MPS-I-S; Mucopolysaccharidosis, MPS-IV-A; Mucopolysaccharidosis, MPS-IV-B; Muenke syndrome; Mulibrey nanism syndrome; Multiple congenital anomalies; Multiple endocrine neoplasia, type 1; Multiple endocrine neoplasia, type 2; Multiple endocrine neoplasia, type 2a; Multiple epiphyseal dysplasia 1; Multiple epiphyseal dysplasia 5; Multiple exostoses type 2; Multiple pterygium syndrome Escobar type; Multiple sulfatase deficiency; Mutilating keratoderma; Myasthenia, limb-girdle, familial; Myasthenic syndrome, congenital, 9, associated with acetylcholine receptor deficiency Myasthenic Syndrome, Congenital, 9, Associated With Acetylcholine Receptor Deficiency; Myasthenic syndrome, congenital, with pre- and postsynaptic defects; Myasthenic syndrome, congenital, with tubular aggregates 2; Myasthenic syndrome, slow-channel congenital; Myoclonic epilepsy myopathy sensory ataxia; Myoclonus, familial cortical; Myofibrillar myopathy 1; Myokymia 1; Myopathy with postural muscle atrophy, X-linked; Myopathy, actin, congenital, with excess of thin myofilaments; Myopathy, centronuclear; Myopathy, distal, 1; Myopathy, isolated mitochondrial, auto somal dominant; Myopathy, reducing body, X-linked, early-onset, severe; Myotonia congenita; Nail disorder, nonsyndromic congenital, 8; Nanophthalmos 4; Narcolepsy 7; Native American myopathy; Navajo neurohepatopathy; Nemaline myopathy 3; Neonatal hypotonia; Neonatal insulin-dependent diabetes mellitus; Neonatal intrahepatic cholestasis caused by citrin deficiency; Neoplasm of ovary; Nephrolithiasis/osteoporosis, hypophosphatemic, 2; Nephronophthisis 16; Nephronophthisis 18; Nephrotic syndrome, type 10; Neu-Laxova syndrome 1; Neurodegeneration with brain iron accumulation 5; Neurohypophyseal diabetes insipidus; Nicolaides-Baraitser syndrome; Niemann-Pick disease type C1; Niemann-Pick disease, type A; Niemann-Pick disease, type B; Niemann-Pick Disease, type c1, juvenile form; Nonaka myopathy; Non-ketotic hyperglycinemia; Noonan syndrome 1; Noonan syndrome 5; Noonan syndrome 7; Noonan syndrome 8; not provided; not specified; Oculocutaneous albinism type 3; Oculopharyngeal muscular dystrophy; Opsismodysplasia; Optic atrophy 9; Optic atrophy and cataract, autosomal dominant; Optic nerve hypoplasia and abnormalities of the central nervous system; Oral-facial-digital syndrome; Ornithine aminotransferase deficiency; Ornithine carbamoyltransferase deficiency; Orofacial cleft 11; Orofaciodigital syndrome 6; Orotic aciduria; Osteogenesis imperfecta type 12; Osteogenesis imperfecta type 13; Osteogenesis imperfecta type III; Osteogenesis imperfecta with normal sclerae, dominant form; Osteogenesis imperfecta, recessive perinatal lethal; Osteopetrosis autosomal dominant type 1; Osteopetrosis autosomal recessive 7; Oto-palato-digital syndrome, type I; Pachydermoperiostosis syndrome; Pallister-Hall syndrome; Papillon-Lef\xc3\xa8vre syndrome; Paragangliomas 1; Paragangliomas 4; Parathyroid carcinoma; Parietal foramina 2; Parkinson disease 1; Parkinson disease 7; Parkinson disease 9; Paroxysmal nocturnal hemoglobinuria 1; Partial hypoxanthine-guanine phosphoribosyltransferase deficiency; Peeling skin syndrome, acral type; Pelger-Hu\xc3\xabt anomaly; Pelizaeus-Merzbacher disease; Pendred syndrome; Permanent neonatal diabetes mellitus; Peroxisome biogenesis disorder 6B; Peroxisome biogenesis disorder 9B; Peutz-Jeghers syndrome; Pfeiffer syndrome; Phenylketonuria; Pheochromocytoma; Phosphoglycerate kinase 1 deficiency; Phosphoribosylpyrophosphate synthetase superactivity; Photosensitive trichothiodystrophy; Pierson syndrome; Pigmentary pallidal degeneration; Pitt-Hopkins syndrome; Pitt-Hopkins-like syndrome 2; Pituitary dependent hypercortisolism; Pituitary hormone deficiency, combined 1; Pituitary hormone deficiency, combined 4; Pituitary hormone deficiency, combined 5; Platelet-type bleeding disorder 16; Polyagglutinable erythrocyte syndrome; Polyarteritis nodosa; Polycystic kidney disease, infantile type; Polyglucosan body myopathy 2; Polymicrogyria, bilateral frontoparietal; Polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataract; Pontocerebellar hypoplasia, type 1B; Pontocerebellar hypoplasia, type 1c; Pontocerebellar hypoplasia, type 9; Poretti-boltshauser syndrome; Preaxial polydactyly 2; Premature chromatid separation trait; Premature ovarian failure 5; Premature ovarian failure 7; Premature ovarian failure 9; Primary autosomal recessive microcephaly 1; Primary autosomal recessive microcephaly 2; Primary autosomal recessive microcephaly 5; Primary autosomal recessive microcephaly 6; Primary ciliary dyskinesia; Primary dilated cardiomyopathy; Primary familial hypertrophic cardiomyopathy; Primary hyperoxaluria, type I; Primary hyperoxaluria, type III; Primary localized cutaneous amyloidosis 1; Primary open angle glaucoma juvenile onset 1; Primary pulmonary hypertension; Primary pulmonary hypertension 4; Primrose syndrome; Progressive myositis ossificans; Progressive sclerosing poliodystrophy; Proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome; Properdin deficiency, X-linked; Propionic acidemia; Pseudo-Hurler polydystrophy; Pseudohypoaldosteronism type 1 autosomal dominant; Pseudohypoaldosteronism type 2B; Pseudohypoaldosteronism, type 2; Pseudohypoparathyroidism type 1A; Pseudoxanthoma elasticum; Pseudoxanthoma elasticum-like disorder with multiple coagulation factor deficiency; Pulmonary arterial hypertension related to hereditary hemorrhagic telangiectasia; Pulmonary Fibrosis And/Or Bone Marrow Failure, Telomere-Related, 2; Pyknodysostosis; Pyridoxine-dependent epilepsy; Pyruvate dehydrogenase E1-alpha deficiency; Radial aplasia-thrombocytopenia syndrome; Raine syndrome; Rasopathy; Recessive dystrophic epidermolysis bullosa; Reifenstein syndrome; Renal carnitine transport defect; Renal cell carcinoma, papillary, 1; Renal dysplasia; Renal hypouricemia 2; Renal tubular acidosis, distal, with hemolytic anemia; Retinal cone dystrophy 3A; Retinitis pigmentosa; Retinitis pigmentosa 10; Retinitis pigmentosa 11; Retinitis pigmentosa 14; Retinitis pigmentosa 2; Retinitis pigmentosa 25; Retinitis pigmentosa 33; Retinitis pigmentosa 35; Retinitis pigmentosa 4; Retinitis pigmentosa 43; Retinitis pigmentosa 50; Retinitis pigmentosa 56; Retinitis Pigmentosa 73; Retinitis Pigmentosa 74; Retinoblastoma; Rett disorder; Rett syndrome, congenital variant; Rett syndrome, zappella variant; Rhabdoid tumor predisposition syndrome 2; Rhizomelic chondrodysplasia punctata type 1; Rienhoff syndrome; Roberts-SC phocomelia syndrome; Robinow syndrome; RRM2B-related mitochondrial disease; Rubinstein-Taybi syndrome; Saethre-Chotzen syndrome; Scapuloperoneal myopathy, X-linked dominant; Schindler disease, type 1; Schindler disease, type 3; Schnyder crystalline corneal dystrophy; Seckel syndrome 1; Seizures; Selective tooth agenesis 1; Senior-Loken Syndrome 8; Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis; SeSAME syndrome; Severe combined immunodeficiency due to ADA deficiency; Severe combined immunodeficiency with microcephaly, growth retardation, and sensitivity to ionizing radiation; Severe congenital neutropenia; Severe congenital neutropenia 4, autosomal recessive; Severe myoclonic epilepsy in infancy; Severe X-linked myotubular myopathy; short QT syndrome; Short QT syndrome 2; Short Stature With Nonspecific Skeletal Abnormalities; Short stature, auditory canal atresia, mandibular hypoplasia, skeletal abnormalities; Short stature, idiopathic, autosomal; Short stature, idiopathic, X-linked; Short-Rib Thoracic Dysplasia 13 With Or Without Polydactyly; Short-rib thoracic dysplasia 14 with polydactyly; Short-rib thoracic dysplasia 3 with or without polydactyly; Shprintzen syndrome; Shprintzen-Goldberg syndrome; Shwachman syndrome; Sialic acid storage disease, severe infantile type; Sialidosis, type II; Sick sinus syndrome 2, autosomal dominant; Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay; Sitosterolemia; Sj\xc3\xb6gren-Larsson syndrome; Smith-Lemli-Opitz syndrome; Sorsby fundus dystrophy; Sotos syndrome 1; Sotos syndrome 2; Spastic ataxia Charlevoix-Saguenay type; Spastic paraplegia 11, autosomal recessive; Spastic paraplegia 30, autosomal recessive; Spastic paraplegia 4, autosomal dominant; Spastic paraplegia 54, autosomal recessive; Spastic paraplegia 6; Spastic paraplegia 7; Spastic paraplegia 8; Spermatogenic failure 8; Spherocytosis type 4; Sphingolipid activator protein 1 deficiency; Sphingomyelin/cholesterol lipidosis; Spinal muscular atrophy, lower extremity predominant 2, autosomal dominant; Spinal muscular atrophy, type II; Spinocerebellar ataxia 14; Spinocerebellar ataxia 21; Spinocerebellar ataxia 35; Spinocerebellar ataxia 38; Spinocerebellar ataxia, autosomal recessive 12; Spondylocostal dysostosis 2; Spondyloepimetaphyseal dysplasia with joint laxity; Spondyloepimetaphyseal dysplasia, pakistani type; Spondyloepiphyseal dysplasia congenita; Spondylometaphyseal dysplasia with cone-rod dystrophy; Squamous cell carcinoma of the head and neck; Stargardt disease 1; Stargardt Disease 3; Steel syndrome; Stickler syndrome type 1; Stiff skin syndrome; Sting-associated vasculopathy, infantile-onset; Subacute neuronopathic Gaucher disease; Succinyl-CoA acetoacetate transferase deficiency; Superoxide dismutase, elevated extracellular; Supravalvar aortic stenosis; Symphalangism-brachydactyly syndrome; Syndactyly type 9; Tangier disease; Tarsal carpal coalition syndrome; Tay-Sachs disease; Tay-Sachs disease, B1 variant; T-cell prolymphocytic leukemia; Temple-Baraitser syndrome; Temtamy preaxial brachydactyly syndrome; Tetralogy of Fallot; Thoracic aortic aneurysms and aortic dissections; Thrombocytopenia 2; Thrombocytopenia, X-linked; Thrombocytopenia, X-linked, intermittent; Thrombophilia due to activated protein C resistance; Thrombophilia, hereditary, due to protein C deficiency, autosomal dominant; Thrombophilia, hereditary, due to protein C deficiency, autosomal recessive; Thyroid Cancer, Nonmedullary, 4; Thyroid dyshormonogenesis 1; Thyrotoxic periodic paralysis; Tietz syndrome; Tooth agenesis, selective, 3; Tooth agenesis, selective, X-linked, 1; Transient neonatal diabetes mellitus 1; Transient neonatal diabetes mellitus 2; Treacher collins syndrome 2; Trichorhinophalangeal dysplasia type I; Triglyceride storage disease with ichthyosis; Triosephosphate isomerase deficiency; Triphalangeal thumb; Tuberous sclerosis 1; Tuberous sclerosis 2; Tuberous sclerosis syndrome; Tyrosinase-negative oculocutaneous albinism; Tyrosinase-positive oculocutaneous albinism; Tyrosinemia type 2; Ullrich congenital muscular dystrophy; Unclassifed; Unverricht-Lundborg syndrome; Upshaw-Schulman syndrome; Uridine 5-prime monophosphate hydrolase deficiency, hemolytic anemia due to; Usher syndrome, type 1D; Usher syndrome, type 1F; Usher syndrome, type 2A; Van der Woude syndrome; Variegate porphyria; Vater association with macrocephaly and ventriculomegaly; Ventricular septal defect 3; Vitamin D-dependent rickets, type 1; Vitamin D-dependent rickets, type 2; Vitamin k-dependent clotting factors, combined deficiency of, 1; Vitelliform dystrophy; Von Hippel-Lindau syndrome; von Willebrand disease, type 2b; Waardenburg syndrome type 1; Waardenburg syndrome type 2E, without neurologic involvement; Waardenburg syndrome type 4A; Waardenburg syndrome type 4B; Waardenburg syndrome type 4C; Walker-Warburg congenital muscular dystrophy; Warburg micro syndrome 3; Warts, hypogammaglobulinemia, infections, and myelokathexis; Werdnig-Hoffmann disease; Werner syndrome; Wieacker syndrome; Wiedemann-Steiner syndrome; Winchester syndrome; Wolfram syndrome 2; Xerocytosis; Xeroderma pigmentosum, group D; Xeroderma pigmentosum, group G; X-linked agammaglobulinemia; X-linked hereditary motor and sensory neuropathy; X-linked ichthyosis with steryl-sulfatase deficiency; X-Linked Mental Retardation 41; X-Linked mental retardation 90; X-linked periventricular heterotopia; Zimmermann-Laband syndrome; or Zimmermann-Laband syndrome 2.

In some embodiments, the target DNA sequence comprises a sequence associated with a disease or disorder. In some embodiments, the target DNA sequence comprises a point mutation associated with a disease or disorder. In some embodiments, the point mutation associated with a disease or disorder is in a gene associated with the disease or disorder. In some embodiments, the gene associated with the disease or disorder is selected from the group consisting of AARS2, AASS, ABCA1, ABCA4, ABCB11, ABCB6, ABCC6, ABCC8, ABCD1, ABCG8, ABHD12, ABHD5, ACADM, ACAT1, ACE, ACO2, ACTA1, ACTB, ACTG1, ACTN2, ACVR1, ACVRL1, ADA, ADAMTS13, ADAR, ADGRG1, ADSL, AFF4, AGA, AGBL1, AGL, AGPAT2, AGRN, AGXT, AIPL1, AKR1D1, ALAD, ALAS2, ALDH3A2, ALDH7A1, ALDOB, ALG1, ALPL, ALS2, ALX3, ALX4, AMPD2, AMT, ANKS6, ANO5, APC, APOA1, APOE, APP, APRT, AQP2, AR, ARHGEF9, ARID2, ARL6, ARSA, ARSB, ARSE, ARX, ASAH1, ASB10, ASPM, ATF6, ATL1, ATM, ATP13A2, ATP1A3, ATP6V1B2, ATP7A, ATR, ATRX, AVP, B2M, B3GALT6, BAAT, BARD1, BBS10, BBS12, BBS2, BBS4, BBS9, BCKDHA, BCKDHB, BCS1L, BEST1, BHLHA9, BICD2, BLM, BMP1, BMP4, BMPR2, BRAF, BRCA1, BRCA2, BRIP1, BTD, BTK, C10orf2, C1GALT1C1, C5orf42, C9, CA1, CACNA1S, CALM2, CANT1, CAPN3, CASK, CASQ2, CASR, CAV3, CBS, CCBE1, CCDC39, CD40LG, CDC6, CDC73, CDH1, CDH23, CDKL5, CDKN2A, CDON, CECR1, CENPJ, CEP120, CEP83, CFP, CFTR, CHAT, CHCHD10, CHD7, CHRNA1, CHRNB2, CHRNG, CHST14, CHSY1, CLCN1, CLCN2, CLCN5, CLCNKA, CLDN16, CLDN19, CLIC2, CLN6, CLN8, CNGA3, CNNM2, CNTNAP2, COA5, COL11A1, COL1A1, COL1A2, COL27A1, COL2A1, COL3A1, COL4A1, COL4A5, COL5A1, COL5A2, COL6A1, COL6A3, COL7A1, COLQ, COMP, CP, CPOX, CPT1A, CPT2, CR2, CRADD, CREBBP, CRH, CRX, CRYAB, CSF1R, CSTB, CTH, CTLA4, CTNS, CTPS1, CTSC, CTSD, CTSF, CTSK, CUL3, CXCR4, CYBB, CYP1B1, CYP27A1, CYP27B1, CYP4F22, CYP4V2, CYP7B1, DARS2, DBT, DCLRE1C, DCX, DDHD2, DES, DGUOK, DHCR24, DHCR7, DKC1, DLG3, DLL4, DMD, DMP1, DNAH11, DNAH5, DNAJB6, DNAJC19, DNM1, DNM2, DNMT1, DOCK6, DOK7, DOLK, DPAGT1, DPM2, DSC2, DSP, DYNC1H1, DYNC2H1, DYRK1A, DYSF, ECEL1, ECHS1, EDA, EDN3, EEF1A2, EFHC1, EFTUD2, EGLN1, EHMT1, EIF2B5, ELN, ELOVL4, ELOVL5, EMP2, ENPP1, EOGT, ERCC2, ERCC8, ESCO2, ETFDH, EXOSC3, EXOSC8, EXT2, EYA1, EYS, F12, F2, F5, F8, F9, FAM20C, FANCA, FANCF, FANCG, FAS, FBLN5, FBN1, FBN2, FBP1, FBXL4, FCGR3B, FGF8, FGFR1, FGFR2, FGFR3, FH, FHL1, FKTN, FLCN, FLG, FLNA, FLNB, FLT4, FLVCR2, FOXC1, FOXE1, FOXG1, FOXL2, FRAS1, FRMD7, FTL, FUS, G6PC3, G6PD, GAA, GABRA1, GABRG2, GAD1, GALC, GALNS, GALT, GAMT, GARS, GATA1, GATA6, GBA, GBA2, GBE1, GCDH, GCH1, GCK, GDAP1, GDI1, GFAP, GGCX, GHR, GJA8, GJB1, GJB2, GK, GLB1, GLI3, GLRA1, GMPPB, GNAI3, GNAS, GNAT1, GNE, GNPTAB, GNPTG, GPI, GPIHBP1, GPT2, GRIA3, GRIN2A, GRIN2B, GRIP1, GRN, GSC, GUCY2D, GYG1, GYS2, H6PD, HADHB, HBB, HBD, HBG1, HBG2, HCN1, HCN4, HESX1, HEXA, HFE, HFM1, HGSNAT, HINT1, HK1, HMGCL, HNF1A, HNF1B, HOGA1, HOXA1, HPD, HPGD, HPRT1, HR, HSD17B10, HSPB1, IDS, IDUA, IFT122, IFT80, IGHMBP2, IKBKG, IL11RA, IL12RB1, IMPDH1, IMPG2, INF2, ING1, INPPL1, INSL3, INSR, IRF6, IRX5, ISPD, ITGA2B, ITGB3, ITK, JAGN1, KCNA1, KCNH1, KCNH2, KCNJ1, KCNJ10, KCNJ11, KCNJ18, KCNJ2, KCNJ5, KCNK3, KCNQ1, KCNQ2, KCNQ4, KDM5C, KIAA0196, KIAA0586, KIF11, KIF1A, KIF2A, KISS1, KISS1R, KLF1, KMT2A, KMT2D, KRAS, KRIT1, KRT1, KRT5, KRT6A, LAMA1, LAMA2, LAMB2, LAMB3, LAMP2, LBR, LCT, LDLR, LIPA, LITAF, LMBR1, LMNA, LPIN2, LPL, LRIT3, LRP5, LRRC6, LRTOMT, LYST, LYZ, MAD1L1, MAF, MALT1, MAN2B1, MAPK1, MASTL, MATN3, MC2R, MCCC1, MCCC2, MCFD2, MCM8, MCOLN1, MCPH1, MECP2, MEF2C, MEFV, MEN1, MESP2, MET, MFN2, MFSD8, MGAT2, MITF, MKKS, MLH1, MLYCD, MMACHC, MMP14, MOG, MPL, MPV17, MPZ, MRE11A, MRPL3, MSH2, MSH6, MSR1, MSX1, MT-ATP6, MTHFR, MTM1, MT-ND1, MTR, MUSK, MUT, MYBPC3, MYC, MYH7, MYL2, MYL3, MYO1E, MYOC, NAGA, NAGLU, NARS2, NBEAL2, NBN, NDP, NDUFA1, NDUFA13, NDUFAF3, NDUFS8, NEFL, NEU1, NEXN, NFIX, NHEJ1, NHLRC1, NIPA1, NIPBL, NKX2-5, NLRP3, NMNAT1, NNT, NOBOX, NOG, NOL3, NOTCH3, NPC1, NPR2, NR0B1, NR3C2, NR5A1, NRXN1, NSD1, NSDHL, NT5C3A, NYX, OAT, OCA2, OCRL, OFD1, OPA3, OPCML, OSMR, OTC, OTOF, OTX2, OXCT1, PAFAH1B1, PAH, PAK3, PALB2, PANK2, PAPSS2, PARK7, PAX2, PAX3, PAX6, PAX9, PCCA, PCCB, PCDH15, PCDH19, PCYT1A, PDE4D, PDE6A, PDE6B, PDE6C, PDE6H, PDGFB, PDHA1, PET100, PEX10, PEX7, PGK1, PGM1, PGM3, PHGDH, PHKB, PHOX2B, PIEZO1, PIGM, PITPNM3, PITX2, PKHD1, PKP2, PLA2G6, PLK4, PLOD1, PLP1, PMM2, PMP22, PMS2, PNPLA6, POLG, POLG2, POLR1A, POLR1D, POLR3A, POLR3B, POMT1, POMT2, POR, POU1F1, PPDX, PPT1, PRKACG, PRKAG2, PRKAR1A, PRKCG, PRNP, PROC, PROK2, PROKR2, PRPF31, PRPS1, PRSS56, PSAP, PSEN1, PTEN, PTPN11, PURA, PVRL4, PYGL, PYGM, RAB18, RAB27A, RAB7A, RAD21, RAD51C, RAF1, RAG2, RAX, RAX2, RB1, RBM8A, RDH12, RET, RHO, RIT1, RNF216, ROGDI, RP2, RPGR, RPS6KA3, RRM2B, RSPO4, RUNX1, RUNX2, RYR1, RYR2, SACS, SAMHD1, SBDS, SCN11A, SCN1A, SCN2A, SCN5A, SCN8A, SCNN1B, SDHAF1, SDHB, SDHD, SEMA4A, SEPN1, SERPINF1, SERPING1, SETBP1, SGCB, SGCD, SH2D1A, SH3TC2, SHANK3, SHH, SHOX, SIGMAR1, SIX3, SKI, SLC11A2, SLC17A5, SLC19A3, SLC1A3, SLC22A5, SLC25A13, SLC25A15, SLC25A19, SLC25A22, SLC25A38, SLC25A4, SLC26A4, SLC2A10, SLC2A9, SLC33A1, SLC35C1, SLC39A4, SLC46A1, SLC4A1, SLC52A2, SLC52A3, SLC5A5, SLC6A5, SLC6A8, SLC9A3R1, SMAD2, SMAD4, SMARCA2, SMARCA4, SMN1, SMPD1, SNCA, SNRNP200, SNRPB, SOD1, SOD3, SOX9, SPAST, SPATA5, SPG11, SPG7, SPTB, SRD5A2, SRY, STAC3, STAR, STAT1, STAT3, STAT5B, STK11, STS, STX1B, STXBP1, SUCLG1, SUMF1, TARDBP, TAZ, TBC1D24, TBX1, TBX20, TCF12, TCF4, TECTA, TERC, TERT, TFAP2B, TFR2, TGFB3, TGFBI, TGFBR2, TGIF1, TGM1, TGM5, TGM6, THRA, THRB, TIMM8A, TK2, TMEM173, TMEM240, TMEM98, TMPRSS15, TMPRSS3, TMPRSS6, TNFRSF11A, TNNI3, TNNT1, TOR1A, TP53, TP63, TPI1, TPM1, TPM2, TPM3, TPO, TPP1, TRIM37, TRNT1, TRPM6, TRPS1, TSC1, TSC2, TSHR, TSPAN12, TTPA, TTR, TUBB4A, TULP1, TYMP, TYR, TYRP1, UBE2T, UBE3A, UBIAD1, UMOD, UMPS, UROD, USH2A, USP8, VDR, VHL, VPS13B, VPS33B, VWF, WAS, WDR19, WDR45, WDR62, WDR72, WFS1, WNK4, WNT5A, WRN, WT1, WWOX, ZBTB20, ZC4H2, ZDHHC9, ZEB2, ZFP57, ZIC3, or ZNF469.

Some embodiments provide methods for using the DNA editing fusion proteins provided herein. In some embodiments, the fusion protein is used to introduce a point mutation into a nucleic acid by deaminating a target nucleobase, e.g., a C residue. In some embodiments, the fusion protein is used to deaminate a target C to U, which is then removed to create an abasic site previously occupied by the C residue. In some embodiments, the deamination of the target nucleobase results in the correction of a genetic defect, e.g., in the correction of a point mutation that leads to a loss of function in a gene product. In some embodiments, the methods provided herein are used to introduce a deactivating point mutation into a gene or allele that encodes a gene product that is associated with a disease or disorder. For example, in some embodiments, methods are provided herein that employ a DNA editing fusion protein to introduce a deactivating point mutation into an oncogene (e.g., in the treatment of a proliferative disease). A deactivating mutation may, in some embodiments, generate a premature stop codon in a coding sequence, which results in the expression of a truncated gene product, e.g., a truncated protein lacking the function of the full-length protein.

In some embodiments, the purpose of the methods provided herein is to restore the function of a dysfunctional gene via genome editing. The nucleobase editing proteins provided herein can be validated for gene editing-based human therapeutics in vitro, e.g., by correcting a disease-associated mutation in human cell culture. It will be understood by the skilled artisan that the nucleobase editing proteins provided herein, e.g., the fusion proteins comprising a nucleic acid programmable DNA binding protein (e.g., Cas9), a cytidine deaminase, and a uracil binding protein can be used to correct any single point C to G or G to C mutation. In the first case, deamination of the mutant C to U, and subsequent excision of the U, corrects the mutation, and in the latter case, deamination of the C to U, and subsequent excision of the U that is base-paired with the mutant G, followed by a round of replication, corrects the mutation.

The successful correction of point mutations in disease-associated genes and alleles opens up new strategies for gene correction with applications in therapeutics and basic research. Site-specific single-base modification systems like the disclosed fusion proteins comprising a nucleic acid programmable DNA binding protein (napDNAbp), a cytidine deaminase, and a uracil binding protein also have applications in “reverse” gene therapy, where certain gene functions are purposely suppressed or abolished. In these cases, site-specifically mutating residues that lead to inactivating mutations in a protein, or mutations that inhibit function of the protein can be used to abolish or inhibit protein function in vitro, ex vivo, or in vivo.

The instant disclosure provides methods for the treatment of a subject diagnosed with a disease associated with or caused by a point mutation that can be corrected by a DNA editing fusion protein provided herein. For example, in some embodiments, a method is provided that comprises administering to a subject having such a disease, e.g., a cancer associated with a point mutation as described above, an effective amount of a base editor fusion protein that corrects the point mutation (e.g., a C to G or G to C point mutation) or introduces a deactivating mutation into a disease-associated gene. In some embodiments, the disease is a proliferative disease. In some embodiments, the disease is a genetic disease. In some embodiments, the disease is a neoplastic disease. In some embodiments, the disease is a metabolic disease. In some embodiments, the disease is a lysosomal storage disease. Other diseases that can be treated by correcting a point mutation or introducing a deactivating mutation into a disease-associated gene will be known to those of skill in the art, and the disclosure is not limited in this respect.

The instant disclosure provides lists of genes comprising pathogenic G to C or C to G mutations. Such pathogenic G to C or C to G mutations may be corrected using the methods and compositions provided herein, for example by mutating the C to a G, and/or the G to a C, thereby restoring gene function.

In some embodiments, a fusion protein recognizes canonical PAMs and therefore can correct the pathogenic G to C or C to G mutations with canonical PAMs, e.g., NGG, respectively, in the flanking sequences. For example, Cas9 proteins that recognize canonical PAMs comprise an amino acid sequence that is at least 80%, 85%, 90%, 95%, 97%, 98%, or 99% identical to the amino acid sequence of Streptococcus pyogenes Cas9 as provided by SEQ ID NO: 6, or to a fragment thereof comprising the RuvC and HNH domains of SEQ ID NO: 6.

It will be apparent to those of skill in the art that in order to target any of the fusion proteins provided herein, comprising a napDNAbp (e.g., a Cas9 domain), to a target site, e.g., a site comprising a point mutation to be edited, it is typically necessary to co-express the fusion protein together with a guide RNA, e.g., an sgRNA. As explained in more detail elsewhere herein, a guide RNA typically comprises a tracrRNA framework allowing for Cas9 binding, and a guide sequence, which confers sequence specificity to the Cas9:nucleic acid editing enzyme/domain fusion protein. In some embodiments, the guide RNA comprises a structure 5′-[guide sequence]-guuuuagagcuagaaauagcaaguuaaaauaaaggcuaguccguuaucaacuugaaaaaguggcaccgagucggugcuu uuu-3′ (SEQ ID NO: 119), wherein the guide sequence comprises a sequence that is complementary to the target sequence. In some embodiments, the guide sequence comprises a nucleic acid sequence that is complementary to a target nucleic acid. The guide sequence is typically 20 nucleotides long. The sequences of suitable guide RNAs for targeting Cas9:nucleic acid editing enzyme/domain fusion proteins to specific genomic target sites will be apparent to those of skill in the art based on the instant disclosure. Such suitable guide RNA sequences typically comprise guide sequences that are complementary to a nucleic sequence within 50 nucleotides upstream or downstream of the target nucleotide to be edited.

Base Editor Efficiency

Some aspects of the disclosure are based on the recognition that any of the base editors provided herein are capable of modifying a specific nucleotide base without generating a significant proportion of indels. An “indel”, as used herein, refers to the insertion or deletion of a nucleotide base within a nucleic acid. Such insertions or deletions can lead to frame shift mutations within a coding region of a gene. In some embodiments, it is desirable to generate base editors that efficiently modify (e.g. mutate or deaminate) a specific nucleotide within a nucleic acid, without generating a large number of insertions or deletions (i.e., indels) in the nucleic acid. In certain embodiments, any of the base editors provided herein are capable of generating a greater proportion of intended modifications (e.g., point mutations or deaminations) versus indels. In some embodiments, the base editors provided herein are capable of generating a ratio of intended point mutations to indels that is greater than 1:1. In some embodiments, the base editors provided herein are capable of generating a ratio of intended point mutations to indels that is at least 1.5:1, at least 2:1, at least 2.5:1, at least 3:1, at least 3.5:1, at least 4:1, at least 4.5:1, at least 5:1, at least 5.5:1, at least 6:1, at least 6.5:1, at least 7:1, at least 7.5:1, at least 8:1, at least 10:1, at least 12:1, at least 15:1, at least 20:1, at least 25:1, at least 30:1, at least 40:1, at least 50:1, at least 100:1, at least 200:1, at least 300:1, at least 400:1, at least 500:1, at least 600:1, at least 700:1, at least 800:1, at least 900:1, or at least 1000:1, or more. The number of intended mutations and indels may be determined using any suitable method, for example the methods used in the below Examples. In some embodiments, to calculate indel frequencies, sequencing reads are scanned for exact matches to two 10-bp sequences that flank both sides of a window in which indels might occur. If no exact matches are located, the read is excluded from analysis. If the length of this indel window exactly matches the reference sequence the read is classified as not containing an indel. If the indel window is two or more bases longer or shorter than the reference sequence, then the sequencing read is classified as an insertion or deletion, respectively.

In some embodiments, the base editors provided herein are capable of limiting formation of indels in a region of a nucleic acid. In some embodiments, the region is at a nucleotide targeted by a base editor or a region within 2, 3, 4, 5, 6, 7, 8, 9, or 10 nucleotides of a nucleotide targeted by a base editor. In some embodiments, any of the base editors provided herein are capable of limiting the formation of indels at a region of a nucleic acid to less than 1%, less than 1.5%, less than 2%, less than 2.5%, less than 3%, less than 3.5%, less than 4%, less than 4.5%, less than 5%, less than 6%, less than 7%, less than 8%, less than 9%, less than 10%, less than 12%, less than 15%, or less than 20%. The number of indels formed at a nucleic acid region may depend on the amount of time a nucleic acid (e.g., a nucleic acid within the genome of a cell) is exposed to a base editor. In some embodiments, an number or proportion of indels is determined after at least 1 hour, at least 2 hours, at least 6 hours, at least 12 hours, at least 24 hours, at least 36 hours, at least 48 hours, at least 3 days, at least 4 days, at least 5 days, at least 7 days, at least 10 days, or at least 14 days of exposing a nucleic acid (e.g., a nucleic acid within the genome of a cell) to a base editor.

Some aspects of the disclosure are based on the recognition that any of the base editors provided herein are capable of efficiently generating an intended mutation, such as a point mutation, in a nucleic acid (e.g. a nucleic acid within a genome of a subject) without generating a significant number of unintended mutations, such as unintended point mutations. In some embodiments, an intended mutation is a mutation that is generated by a specific base editor bound to a gRNA, specifically designed to generate the intended mutation. In some embodiments, the intended mutation is a mutation associated with a disease or disorder. In some embodiments, the intended mutation is a cytosine (C) to guanine (G) point mutation associated with a disease or disorder. In some embodiments, the intended mutation is a guanine (G) to cytosine (C) point mutation associated with a disease or disorder. In some embodiments, the intended mutation is a cytosine (C) to guanine (G) point mutation within the coding region of a gene. In some embodiments, the intended mutation is a Guanine (G) to cytosine (C) point mutation within the coding region of a gene. In some embodiments, the intended mutation is a point mutation that generates a stop codon, for example, a premature stop codon within the coding region of a gene. In some embodiments, the intended mutation is a mutation that eliminates a stop codon. In some embodiments, the intended mutation is a mutation that alters the splicing of a gene. In some embodiments, the intended mutation is a mutation that alters the regulatory sequence of a gene (e.g., a gene promotor or gene repressor). In some embodiments, any of the base editors provided herein are capable of generating a ratio of intended mutations to unintended mutations (e.g., intended point mutations:unintended point mutations) that is greater than 1:1. In some embodiments, any of the base editors provided herein are capable of generating a ratio of intended mutations to unintended mutations (e.g., intended point mutations:unintended point mutations) that is at least 1.5:1, at least 2:1, at least 2.5:1, at least 3:1, at least 3.5:1, at least 4:1, at least 4.5:1, at least 5:1, at least 5.5:1, at least 6:1, at least 6.5:1, at least 7:1, at least 7.5:1, at least 8:1, at least 10:1, at least 12:1, at least 15:1, at least 20:1, at least 25:1, at least 30:1, at least 40:1, at least 50:1, at least 100:1, at least 150:1, at least 200:1, at least 250:1, at least 500:1, or at least 1000:1, or more. It should be appreciated that the characteristics of the base editors described in the “Base Editor Efficiency” section, herein, may be applied to any of the fusion proteins, or methods of using the fusion proteins provided herein.

Methods for Editing Nucleic Acids

Some aspects of the disclosure provide methods for editing a nucleic acid. In some embodiments, the method is a method for editing a nucleobase of a nucleic acid (e.g., a base pair of a double-stranded DNA sequence). In some embodiments, the method comprises the steps of: a) contacting a target region of a nucleic acid (e.g., a double-stranded DNA sequence) with a complex comprising a base editor (e.g., a Cas9 domain fused to a cytidine deaminase and a uracil binding protein) and a guide nucleic acid (e.g., gRNA), wherein the target region comprises a targeted nucleobase pair, b) inducing strand separation of said target region, c) converting a first nucleobase of said target nucleobase pair in a single strand of the target region to a second nucleobase, d) excising the second nucleobase, thereby creating an abasic site, and e) replacing a third nucleobase complementary to the first nucleobase base with a fourth nucleobase that is a cytosine (C). In some embodiments, the method results in less than 20% indel formation in the nucleic acid. It should be appreciated that in some embodiments, step b is omitted. In some embodiments, the first nucleobase is a cytosine (C). In some embodiments, the second nucleobase is a deaminated cytosine, or uracil. In some embodiments, the third nucleobase is a guanine (G). In some embodiments, the fourth nucleobase is a cytosine (C). In some embodiments, a fifth nucleobase is ligated into the abasic site generated in step (d). In some embodiments the fifth nucleobase is guanine (G). In some embodiments, the method results in less than 19%, 18%, 16%, 14%, 12%, 10%, 8%, 6%, 4%, 2%, 1%, 0.5%, 0.2%, or less than 0.1% indel formation. In some embodiments, at least 5% of the intended base pairs are edited. In some embodiments, at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% of the intended base pairs are edited.

In some embodiments, the ratio of intended products to unintended products in the target nucleotide is at least 2:1, 5:1, 10:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, 100:1, or 200:1, or more. In some embodiments, the ratio of intended point mutation to indel formation is greater than 1:1, 10:1, 50:1, 100:1, 500:1, or 1000:1, or more. In some embodiments, the cut single strand (nicked strand) is hybridized to the guide nucleic acid. In some embodiments, the cut single strand is opposite to the strand comprising the first nucleobase. In some embodiments, the base editor comprises a Cas9 domain. In some embodiments, the base editor comprises nickase activity. In some embodiments, the intended edited base pair is upstream of a PAM site. In some embodiments, the intended edited base pair is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 nucleotides upstream of the PAM site. In some embodiments, the intended edited basepair is downstream of a PAM site. In some embodiments, the intended edited base pair is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 nucleotides downstream stream of the PAM site. In some embodiments, the method does not require a canonical (e.g., NGG) PAM site. In some embodiments, the nucleobase editor comprises a linker. In some embodiments, the linker is 1-25 amino acids in length. In some embodiments, the linker is 5-20 amino acids in length. In some embodiments, linker is 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acids in length. In some embodiments, the target region comprises a target window, wherein the target window comprises the target nucleobase pair. In some embodiments, the target window comprises 1-10 nucleotides. In some embodiments, the target window is 1-9, 1-8, 1-7, 1-6, 1-5, 1-4, 1-3, 1-2, or 1 nucleotides in length. In some embodiments, the target window is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 nucleotides in length. In some embodiments, the intended edited base pair is within the target window. In some embodiments, the target window comprises the intended edited base pair. In some embodiments, the method is performed using any of the base editors provided herein. In some embodiments, a target window is a deamination window.

In some embodiments, the disclosure provides methods for editing a nucleotide. In some embodiments, the disclosure provides a method for editing a nucleobase pair of a double-stranded DNA sequence. In some embodiments, the method comprises a) contacting a target region of the double-stranded DNA sequence with a complex comprising a base editor and a guide nucleic acid (e.g., gRNA), where the target region comprises a target nucleobase pair, b) inducing strand separation of said target region, c) converting a first nucleobase of said target nucleobase pair in a single strand of the target region to a second nucleobase, d) excising the second nucleobase, thereby creating an abasic site, and e) replacing a third nucleobase complementary to the first nucleobase base with a fourth nucleobase that is a cytosine (C), thereby generating an intended edited base pair, wherein the efficiency of generating the intended edited base pair is at least 5%. It should be appreciated that in some embodiments, step b is omitted. In some embodiments, at least 5% of the intended base pairs are edited. In some embodiments, at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% of the intended base pairs are edited. In some embodiments, the method causes less than 19%, 18%, 16%, 14%, 12%, 10%, 8%, 6%, 4%, 2%, 1%, 0.5%, 0.2%, or less than 0.1% indel formation. In some embodiments, the ratio of intended product to unintended products at the target nucleotide is at least 2:1, 5:1, 10:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, 100:1, or 200:1, or more. In some embodiments, the ratio of intended point mutation to indel formation is greater than 1:1, 10:1, 50:1, 100:1, 500:1, or 1000:1, or more. In some embodiments, the cut single strand is hybridized to the guide nucleic acid. In some embodiments, the nucleobase editor comprises nickase activity. In some embodiments, the intended edited base pair is upstream of a PAM site. In some embodiments, the intended edited base pair is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 nucleotides upstream of the PAM site. In some embodiments, the intended edited basepair is downstream of a PAM site. In some embodiments, the intended edited base pair is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 nucleotides downstream stream of the PAM site. In some embodiments, the method does not require a canonical (e.g., NGG) PAM site. In some embodiments, the nucleobase editor comprises a linker. In some embodiments, the linker is 1-25 amino acids in length. In some embodiments, the linker is 5-20 amino acids in length. In some embodiments, the linker is 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acids in length. In some embodiments, the target region comprises a target window, wherein the target window comprises the target nucleobase pair. In some embodiments, the target window comprises 1-10 nucleotides. In some embodiments, the target window is 1-9, 1-8, 1-7, 1-6, 1-5, 1-4, 1-3, 1-2, or 1 nucleotides in length. In some embodiments, the target window is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 nucleotides in length. In some embodiments, the intended edited base pair occurs within the target window. In some embodiments, the target window comprises the intended edited base pair. In some embodiments, the nucleobase editor is any one of the base editors provided herein.

Pharmaceutical Compositions

Other aspects of the present disclosure relate to pharmaceutical compositions comprising any of the base editors, fusion proteins, or the fusion protein-gRNA complexes described herein. The term “pharmaceutical composition”, as used herein, refers to a composition formulated for pharmaceutical use. In some embodiments, the pharmaceutical composition further comprises a pharmaceutically acceptable carrier. In some embodiments, the pharmaceutical composition comprises additional agents (e.g. for specific delivery, increasing half-life, or other therapeutic compounds).

As used here, the term “pharmaceutically-acceptable carrier” means a pharmaceutically-acceptable material, composition or vehicle, such as a liquid or solid filler, diluent, excipient, manufacturing aid (e.g., lubricant, talc magnesium, calcium or zinc stearate, or steric acid), or solvent encapsulating material, involved in carrying or transporting the compound from one site (e.g., the delivery site) of the body, to another site (e.g., organ, tissue or portion of the body). A pharmaceutically acceptable carrier is “acceptable” in the sense of being compatible with the other ingredients of the formulation and not injurious to the tissue of the subject (e.g., physiologically compatible, sterile, physiologic pH, etc.). Some examples of materials which can serve as pharmaceutically-acceptable carriers include: (1) sugars, such as lactose, glucose and sucrose; (2) starches, such as corn starch and potato starch; (3) cellulose, and its derivatives, such as sodium carboxymethyl cellulose, methylcellulose, ethyl cellulose, microcrystalline cellulose and cellulose acetate; (4) powdered tragacanth; (5) malt; (6) gelatin; (7) lubricating agents, such as magnesium stearate, sodium lauryl sulfate and talc; (8) excipients, such as cocoa butter and suppository waxes; (9) oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil and soybean oil; (10) glycols, such as propylene glycol; (11) polyols, such as glycerin, sorbitol, mannitol and polyethylene glycol (PEG); (12) esters, such as ethyl oleate and ethyl laurate; (13) agar; (14) buffering agents, such as magnesium hydroxide and aluminum hydroxide; (15) alginic acid; (16) pyrogen-free water; (17) isotonic saline; (18) Ringer's solution; (19) ethyl alcohol; (20) pH buffered solutions; (21) polyesters, polycarbonates and/or polyanhydrides; (22) bulking agents, such as polypeptides and amino acids (23) serum component, such as serum albumin, HDL and LDL; (22) C2-C12 alcohols, such as ethanol; and (23) other non-toxic compatible substances employed in pharmaceutical formulations. Wetting agents, coloring agents, release agents, coating agents, sweetening agents, flavoring agents, perfuming agents, preservative and antioxidants can also be present in the formulation. The terms such as “excipient”, “carrier”, “pharmaceutically acceptable carrier” or the like are used interchangeably herein.

In some embodiments, the pharmaceutical composition is formulated for delivery to a subject, e.g., for gene editing. Suitable routes of administrating the pharmaceutical composition described herein include, without limitation: topical, subcutaneous, transdermal, intradermal, intralesional, intraarticular, intraperitoneal, intravesical, transmucosal, gingival, intradental, intracochlear, transtympanic, intraorgan, epidural, intrathecal, intramuscular, intravenous, intravascular, intraosseus, periocular, intratumoral, intracerebral, and intracerebroventricular administration.

In some embodiments, the pharmaceutical composition described herein is administered locally to a diseased site (e.g., tumor site). In some embodiments, the pharmaceutical composition described herein is administered to a subject by injection, by means of a catheter, by means of a suppository, or by means of an implant, the implant being of a porous, non-porous, or gelatinous material, including a membrane, such as a sialastic membrane, or a fiber.

In other embodiments, the pharmaceutical composition described herein is delivered in a controlled release system. In one embodiment, a pump may be used (see, e.g., Langer, 1990, Science 249:1527-1533; Sefton, 1989, CRC Crit. Ref. Biomed. Eng. 14:201; Buchwald et al., 1980, Surgery 88:507; Saudek et al., 1989, N. Engl. J. Med. 321:574). In another embodiment, polymeric materials can be used. (See, e.g., Medical Applications of Controlled Release (Langer and Wise eds., CRC Press, Boca Raton, Fla., 1974); Controlled Drug Bioavailability, Drug Product Design and Performance (Smolen and Ball eds., Wiley, New York, 1984); Ranger and Peppas, 1983, Macromol. Sci. Rev. Macromol. Chem. 23:61. See also Levy et al., 1985, Science 228:190; During et al., 1989, Ann. Neurol. 25:351; Howard et al., 1989, J. Neurosurg. 71:105.) Other controlled release systems are discussed, for example, in Langer, supra.

In some embodiments, the pharmaceutical composition is formulated in accordance with routine procedures as a composition adapted for intravenous or subcutaneous administration to a subject, e.g., a human. In some embodiments, pharmaceutical compositions for administration by injection are solutions in sterile isotonic aqueous buffer. Where necessary, the pharmaceutical can also include a solubilizing agent and a local anesthetic such as lignocaine to ease pain at the site of the injection. Generally, the ingredients are supplied either separately or mixed together in unit dosage form, for example, as a dry lyophilized powder or water free concentrate in a hermetically sealed container such as an ampoule or sachette indicating the quantity of active agent. Where the pharmaceutical is to be administered by infusion, it can be dispensed with an infusion bottle containing sterile pharmaceutical grade water or saline. Where the pharmaceutical composition is administered by injection, an ampoule of sterile water for injection or saline can be provided so that the ingredients can be mixed prior to administration.

A pharmaceutical composition for systemic administration may be a liquid, e.g., sterile saline, lactated Ringer's or Hank's solution. In addition, the pharmaceutical composition can be in solid forms and re-dissolved or suspended immediately prior to use. Lyophilized forms are also contemplated.

The pharmaceutical composition can be contained within a lipid particle or vesicle, such as a liposome or microcrystal, which is also suitable for parenteral administration. The particles can be of any suitable structure, such as unilamellar or plurilamellar, so long as compositions are contained therein. Compounds can be entrapped in “stabilized plasmid-lipid particles” (SPLP) containing the fusogenic lipid dioleoylphosphatidylethanolamine (DOPE), low levels (5-10 mol %) of cationic lipid, and stabilized by a polyethyleneglycol (PEG) coating (Zhang Y. P. et al., Gene Ther. 1999, 6:1438-47). Positively charged lipids such as N-[1-(2,3-dioleoyloxi)propyl]-N,N,N-trimethyl-amoniummethylsulfate, or “DOTAP,” are particularly preferred for such particles and vesicles. The preparation of such lipid particles is well known. See, e.g., U.S. Pat. Nos. 4,880,635; 4,906,477; 4,911,928; 4,917,951; 4,920,016; and 4,921,757; each of which is incorporated herein by reference.

The pharmaceutical composition described herein may be administered or packaged as a unit dose, for example. The term “unit dose” when used in reference to a pharmaceutical composition of the present disclosure refers to physically discrete units suitable as unitary dosage for the subject, each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect in association with the required diluent; i.e., carrier, or vehicle.

Further, the pharmaceutical composition can be provided as a pharmaceutical kit comprising (a) a container containing a compound of the invention (e.g., a fusion protein or a base editor) in lyophilized form and (b) a second container containing a pharmaceutically acceptable diluent (e.g., sterile water) for injection. The pharmaceutically acceptable diluent can be used for reconstitution or dilution of the lyophilized compound of the invention. Optionally associated with such container(s) can be a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, which notice reflects approval by the agency of manufacture, use or sale for human administration.

In another aspect, an article of manufacture containing materials useful for the treatment of the diseases described above is included. In some embodiments, the article of manufacture comprises a container and a label. Suitable containers include, for example, bottles, vials, syringes, and test tubes. The containers may be formed from a variety of materials such as glass or plastic. In some embodiments, the container holds a composition that is effective for treating a disease described herein and may have a sterile access port. For example, the container may be an intravenous solution bag or a vial having a stopper pierceable by a hypodermic injection needle. The active agent in the composition is a compound of the invention. In some embodiments, the label on or associated with the container indicates that the composition is used for treating the disease of choice. The article of manufacture may further comprise a second container comprising a pharmaceutically-acceptable buffer, such as phosphate-buffered saline, Ringer's solution, or dextrose solution. It may further include other materials desirable from a commercial and user standpoint, including other buffers, diluents, filters, needles, syringes, and package inserts with instructions for use.

Kits, Vectors, Cells

Some aspects of this disclosure provide kits comprising a nucleic acid construct, comprising (a) a nucleotide sequence encoding any of the fusion protein as provided herein; and (b) a heterologous promoter that drives expression of the sequence of (a). In some embodiments, the kit further comprises an expression construct encoding a guide RNA backbone, wherein the construct comprises a cloning site positioned to allow the cloning of a nucleic acid sequence identical or complementary to a target sequence into the guide RNA backbone.

Some aspects of this disclosure provide polynucleotides encoding a napDNAbp (e.g., Cas9 protein) of a fusion protein as provided herein. Some aspects of this disclosure provide vectors comprising such polynucleotides. In some embodiments, the vector comprises a heterologous promoter driving expression of polynucleotide.

Some aspects of this disclosure provide cells comprising any of the fusion proteins provided herein, a nucleic acid molecule encoding any of the fusion proteins provided herein, a complex comprising any of the fusion proteins provided herein and a gRNA, and/or any of the vectors provided herein.

The description of exemplary embodiments of the reporter systems above is provided for illustration purposes only and not meant to be limiting. Additional reporter systems, e.g., variations of the exemplary systems described in detail above, are also embraced by this disclosure.

EXAMPLES

Cytosine (C) to Guanine (G) Base Editors Through Abasic Site Generation and Engineered Specific Repair

Sequencing data for the HEK2, RNF2, and FANCF sites is given below. Data presented represents base editing values for the most edited C in the window. This is C6 for HEK2, C6 for RNF2, and C6 for FANCF. The sequences for the three different sites before and after base editing are as follows: HEK2: GAACACAAAGCATAGACTGC (SEQ ID NO: 110) (sequencing reads CTTGTGTTTCGTATCTGACG (SEQ ID NO: 111)); RNF2: GTCATCTTAGTCATTACCTG (SEQ ID NO: 112) (sequencing reads CAGTAGAATCAGTAATGGAC (SEQ ID NO: 113)); and FANCF: GGAATCCCTTCTGCAGCACC (SEQ ID NO: 114) (sequencing reads the same). For both HEK2 and RNF2, the non-target strand was sequenced (this strand contains G's complementary to the target C's). For FANCF the target strand was sequenced (this strand contains the target C's). A schematic for C to T base editing (e.g., using BE3, which is a C to T base editor) and C to G base editing is shown in FIGS. 1 and 2 . Certain DNA polymerases are known to replace bases opposite abasic sites with G. One strategy to achieve C to G base editing is to induce the creation of the abasic site, then recruit or tether such a polymerase to replace the G opposite the abasic site with a C. This could provide access to all editors, if C and T can be excised and repaired with all the polymerases based on the polymerases' predetermined base preferences.

Different fusion constructs are summarized below and are shown in Table 1. UdgX is an isoform of UDG known to bind tightly to uracil with minimal uracil-excision activity. UdgX* is a mutated version of UdgX (Sang et al. NAR, 2015) that was observed to lack uracil excision activity by an in vitro assay in Sang et al. UdgX_On is another mutated version of UdgX (Sang et al. NAR, 2015) observed to have an increased uracil excision activity in the same in vitro assay reported in Sang et al. UDG is the enzyme responsible for the excision of uracil from DNA to create an abasic site. Rev7 is a component of the Rev1/Rev3/Rev7 complex known to incorporate C opposite an abasic site. Rev1 is the enzymatic component of the above mentioned complex. Polymerases Alpha, Beta, Gamma, Delta, Epsilon, Gamma, Eta, Iota, Kappa, Lambda, Mu, and Nu are eukaryotic polymerases with different preferences for base incorporation opposite an abasic site.

TABLE 1 Construct Reference Key Construct Definition BE3 Published base editing construct BE3_UdgX UGI replaced with Uracil binding protein, UdgX BE3_UdgX* UGI replaced with UdgX isoform with diminished binding affinity to Uracil BE3_REV7 UGI replaced with a component of C-integrating translesion synthesis machinery BE2_UDG dCas9 based construct (no nicking) where UGI is replaced with uracil deglycosylase BE3_UDG UGI is replaced with uracil deglycosylase (BE3) BE2_UdgX_On dCas9 construct where UGI is replaced with UdgX with an activating mutation that increases Uracil excision BE3_UdgX_On UGI replaced with UdgX with an activating mutation that increases Uracil excision SMUG1 UGI replaced with SMUG1, a ssDNA uracil deglycosylase Constructs Used in the Examples: BE3_Full Length—This is a C to T base editor construct comprising a cytidine deaminase, a nCas9, and a uracil glycosylase inhibitor (UGI) domain.

(SEQ ID NO: 115) MSSETGPVAVDPTLRRRIEPHEFEVFFDPRELRKETCLLYEINWGGRHS IWRHTSQNTNKHVEVNFIEKFTTERYFCPNTRCSITWFLSWSPCGECSR AITEFLSRYPHVTLFIYIARLYHHADPRNRQGLRDLISSGVTIQIMTEQ ESGYCWRNFVNYSPSNEAHWPRYPHLWVRLYVLELYCIILGLPPCLNIL RRKQPQLTFFTIALQSCHYQRLPPHILWATGLKSGSETPGTSESATPES DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGA LLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFH RLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDK ADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFE ENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSL GLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKN LSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLP EKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKL NREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEK ILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSF IERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVETSGVEDRFNA SLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKT YAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDG FANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKG ILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIE EGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLS DYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYW RQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVA QILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNY HHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIG KATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRD FATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDP KKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKN PIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNEL ALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAF KYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGDSGGST NLSDIIEKETGKQLVIQESILMLPEEVEEVIGNKPESDILVHTAYDEST DENVMLLTSDAPEYKPWALVIQDSNGENKIKMLSGGSPKKKRKV BE3_No UGI—This construct is the above BE3 construct, lacking the UGI domain.

(SEQ ID NO: 116) MSSETGPVAVDPTLRRRIEPHEFEVFFDPRELRKETCLLYEINWGGRHS IWRHTSQNTNKHVEVNFIEKFTTERYFCPNTRCSITWFLSWSPCGECSR AITEFLSRYPHVTLFIYIARLYHHADPRNRQGLRDLISSGVTIQIMTEQ ESGYCWRNFVNYSPSNEAHWPRYPHLWVRLYVLELYCIILGLPPCLNIL RRKQPQLTFFTIALQSCHYQRLPPHILWATGLKSGSETPGTSESATPES DKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGA LLFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFH RLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDK ADLRLIYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFE ENPINASGVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSL GLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKN LSDAILLSDILRVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLP EKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKL NREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEK ILTFRIPYYVGPLARGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSF IERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFL SGEQKKAIVDLLFKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDRFNA SLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFEDREMIEERLKT YAHLFDDKVMKQLKRRRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDG FANRNFMQLIHDDSLTFKEDIQKAQVSGQGDSLHEHIANLAGSPAIKKG ILQTVKVVDELVKVMGRHKPENIVIEMARENQTTQKGQKNSRERMKRIE EGIKELGSQILKEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLS DYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYW RQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVA QILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNY HHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIG KATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRD FATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDP KKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSSFEKN PIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGNEL ALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAF KYFDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD Cas9 Nickase Sequence—Used in BE3.

(SEQ ID NO: 21) MDKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGAL LFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLE ESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRL IYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINAS GVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSLGLTPNFKSN FDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKNLSDAILLSDIL RVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLPEKYKEIFFDQSKN GYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLLRKQRTFDNG SIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARGN SRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPK HSLLYEYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTV KQLKEDYFKKIECFDSVEISGVEDRFNASLGTYHDLLKIIKDKDFLDNEEN EDILEDIVLTLTLFEDREMIEERLKTYAHLFDDKVMKQLKRRRYTGWGRLS RKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDDSLTFKEDIQKAQVS GQGDSLHEHIANLAGSPAIKKGILQTVKVVDELVKVMGRHKPENIVIEMAR ENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVENTQLQNEKLYLYYL QNGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKVLTRSDKNRGKS DNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIK RQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKD FQFYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRK MIAKSEQEIGKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGE IVWDKGRDFATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIAR KKDWDPKKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSS FEKNPIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGN ELALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAFKY FDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD dCas9 Sequence—Used in BE2

(SEQ ID NO: 22) MDKKYSIGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGAL LFDSGETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLE ESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRL IYLALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINAS GVDAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSLGLTPNFKSN FDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKNLSDAILLSDIL RVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLPEKYKEIFFDQSKN GYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLLRKQRTFDNG SIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARGN SRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPK HSLLYEYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTV KQLKEDYFKKIECFDSVEISGVEDRFNASLGTYHDLLKIIKDKDFLDNEEN EDILEDIVLTLTLFEDREMIEERLKTYAHLFDDKVMKQLKRRRYTGWGRLS RKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDDSLTFKEDIQKAQVS GQGDSLHEHIANLAGSPAIKKGILQTVKVVDELVKVMGRHKPENIVIEMAR ENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVENTQLQNEKLYLYYL QNGRDMYVDQELDINRLSDYDVDAIVPQSFLKDDSIDNKVLTRSDKNRGKS DNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERGGLSELDKAGFIK RQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVITLKSKLVSDFRKD FQFYKVREINNYHHAHDAYLNAVVGTALIKKYPKLESEFVYGDYKVYDVRK MIAKSEQEIGKATAKYFFYSNIMNFFKTEITLANGEIRKRPLIETNGETGE IVWDKGRDFATVRKVLSMPQVNIVKKTEVQTGGFSKESILPKRNSDKLIAR KKDWDPKKYGGFDSPTVAYSVLVVAKVEKGKSKKLKSVKELLGITIMERSS FEKNPIDFLEAKGYKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKGN ELALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEIIEQISE FSKRVILADANLDKVLSAYNKHRDKPIREQAENIIHLFTLTNLGAPAAFKY FDTTIDRKRYTSTKEVLDATLIHQSITGLYETRIDLSQLGGD BE3_Replace UGI with UDG, UdgX variants, Polymerases—In the below construct, the NLS sequence is identified by underlining and linkers are identified in italics. The “[UGI]” indicated in the sequence below identifies the location where UDG, UDG variants (e.g., UDG, UdgX* (R107S), and UdgX_On (H109S)), Rev7, and Smug1, were inserted (rather than the UGI of BE3). The “[Polymerase]” indicated in the sequence below identifies the location where polymerases (e.g., Pol Beta, Pol Lambda, Pol Eta, Pol Mu, Pol Iota, Pol Kappa, Pol Alpha, Pol Delta, Pol Gamma, and Pol Nu), and Rev1 were inserted.

(SEQ ID NO: 117) MSSETGPVAVDPTLRRRIEPHEFEVFFDPRELRKETCLLYEINWGGRHSI WRHTSQNTNKHVEVNFIEKFTTERYFCPNTRCSITWFLSWSPCGECSRAI TEFLSRYPHVTLFIYIARLYHHADPRNRQGLRDLISSGVTIQIMTEQESG YCWRNFVNYSPSNEAHWPRYPHLWVRLYVLELYCIILGLPPCLNILRRKQ PQLTFFTIALQSCHYQRLPPHILWATGLKSGSETPGTSESATPESDKKYS IGLAIGTNSVGWAVITDEYKVPSKKFKVLGNTDRHSIKKNLIGALLFDSG ETAEATRLKRTARRRYTRRKNRICYLQEIFSNEMAKVDDSFFHRLEESFL VEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRLIYL ALAHMIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINASGV DAKAILSARLSKSRRLENLIAQLPGEKKNGLFGNLIALSLGLTPNFKSNF DLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKNLSDAILLSDIL RVNTEITKAPLSASMIKRYDEHHQDLTLLKALVRQQLPEKYKEIFFDQSK NGYAGYIDGGASQEEFYKFIKPILEKMDGTEELLVKLNREDLLRKQRTFD NGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLA RGNSRFAWMTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEK VLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTN RKVTVKQLKEDYFKKIECFDSVEISGVEDRFNASLGTYHDLLKIIKDKDF LDNEENEDILEDIVLTLTLFEDREMIEERLKTYAHLFDDKVMKQLKRRRY TGWGRLSRKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDDSLTFKE DIQKAQVSGQGDSLHEHIANLAGSPAIKKGILQTVKVVDELVKVMGRHKP ENIVIEMARENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVENTQL QNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKV LTRSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAERG GLSELDKAGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVKVI TLKSKLVSDFRKDFQFYKVREINNYHHAHDAYLNAVVGTALIKKYPKLES EFVYGDYKVYDVRKMIAKSEQEIGKATAKYFFYSNIMNFFKTEITLANGE IRKRPLIETNGETGEIVWDKGRDFATVRKVLSMPQVNIVKKTEVQTGGFS KESILPKRNSDKLQNEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVP QSFLKDDSIDNKVLTRSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLIT QRKFDNLTKAERGGLSELDKAGFIKRQLVETRQITKHVAQILDSRMNTKY DENDKLIREVKVITLKSKLVSDFRKDFQFYKVREINNYHHAHDAYLNAVV GTALIKKYPKLESEFVYGDYKVYDVRKMIAKSEQEIGKATAKYFFYSNIM NFFKTEITLANGEIRKRPLIETNGETGEIVWDKGRDFATVRKVLSMPQVN IVKKTEVQTGGFSKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVAYSV LVVAKVEKGKSKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKD LIIKLPKYSLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYE KLKGSPEDNEQKQLFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSA YNKHRDKPIREQAENIIHLFTLTNLGAPAAFKYFDTTIDRKRYTSTKEVL DATLIHQSITGLYETRIDLSQLGGDSGGS (SEQ ID NO: 120) [UGI]SGGSGGSGGS (SEQ ID NO: 41) [Polymerase]PKKKRKV  N-terminal UDG (insert UDG (Tyr147A1a) or UDG (Asn204Asp))+Cas9 nickase and Polymerase at C-terminus—In the below construct, the NLS sequence is identified by underlining and linkers are identified in italics. The “[UDGvariants]” indicated in the sequence below identifies the location where UDG Tyr147Ala and UDG Asn204Asp, were inserted. The “[Polymerase]” indicated in the sequence below identifies the location where polymerases (e.g., Pol Beta, Pol Lambda, Pol Eta, Pol Mu, Pol Iota, Pol Kappa, Pol Alpha, Pol Delta, Pol Gamma, and Pol Nu), and Rev1 were inserted.

(SEQ ID NO: 118) [UDGvariants]SETPGTSESATPESDKKYSIGLAIGTNSVGWAVITD EYKVPSKKFKVLGNTDRHSIKKNLIGALLFDSGETAEATRLKRTARRRY TRRKNRICYLQEIFSNEMAKVDDSFFHRLEESFLVEEDKKHERHPIFGN IVDEVAYHEKYPTIYHLRKKLVDSTDKADLRLIYLALAHMIKFRGHFLI EGDLNPDNSDVDKLFIQLVQTYNQLFEENPINASGVDAKAILSARLSKS RRLENLIAQLPGEKKNGLFGNLIALSLGLTPNFKSNFDLAEDAKLQLSK DTYDDDLDNLLAQIGDQYADLFLAAKNLSDAILLSDILRVNTEITKAPL SASMIKRYDEHHQDLTLLKALVRQQLPEKYKEIFFDQSKNGYAGYIDGG ASQEEFYKFIKPILEKMDGTEELLVKLNREDLLRKQRTFDNGSIPHQIH LGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARGNSRFAW MTRKSEETITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPKHSL LYEYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDLLFKTNRKVTVK QLKEDYFKKIECFDSVEISGVEDRFNASLGTYHDLLKIIKDKDFLDNEE NEDILEDIVLTLTLFEDREMIEERLKTYAHLFDDKVMKQLKRRRYTGWG RLSRKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDDSLTFKEDIQ KAQVSGQGDSLHEHIANLAGSPAIKKGILQTVKVVDELVKVMGRHKPEN IVIEMARENQTTQKGQKNSRERMKRIEEGIKELGSQILKEHPVENTQLQ NEKLYLYYLQNGRDMYVDQELDINRLSDYDVDHIVPQSFLKDDSIDNKV LTRSDKNRGKSDNVPSEEVVKKMKNYWRQLLNAKLITQRKFDNLTKAER GGLSELDKAGFIKRQLVETRQITKHVAQILDSRMNTKYDENDKLIREVK VITLKSKLVSDFRKDFQFYKVREINNYHHAHDAYLNAVVGTALIKKYPK LESEFVYGDYKVYDVRKMIAKSEQEIGKATAKYFFYSNIMNFFKTEITL ANGEIRKRPLIETNGETGEIVWDKGRDFATVRKVLSMPQVNIVKKTEVQ TGGFSKESILPKRNSDKLIARKKDWDPKKYGGFDSPTVAYSVLVVAKVE KGKSKKLKSVKELLGITIMERSSFEKNPIDFLEAKGYKEVKKDLIIKLP KYSLFELENGRKRMLASAGELQKGNELALPSKYVNFLYLASHYEKLKGS PEDNEQKQLFVEQHKHYLDEIIEQISEFSKRVILADANLDKVLSAYNKH RDKPIREQAENIIHLFTLTNLGAPAAFKYFDTTIDRKRYTSTKEVLDAT LIHQSITGLYETRIDLSQLGGDSGGS (SEQ ID NO: 41) [Polymerase]PKKKRKV

Example 1: C to G Approach 1—Increase Abasic Site Formation

If an abasic site is more efficiently generated, it is expected that the total flux through the C to G base editing pathway will be increased. A schematic representation of base editors used in this approach is shown in FIGS. 3 and 4 . Using UdgX, an orthologue of UDG identified to bind tightly to Uracil with minimal uracil excising activity, increases the amount of C to G editing. Without wishing to be bound by any particular theory, UdgX near-covalent binding to U mimics a lesion that instigates translesion polymerase-type repair. Further, UdgX has a low level catalytic activity which, in combination with tight binding, excises the U and leads to abasic site formation. Abasic site formation allows for off-target products and preferential generation of this lesion leads to more product. This is supported through different experiments and base editors, which are illustrated in FIGS. 5 and 6 .

The results of C to G base editing at HEK2, RNF2, and FANCF sites in WT cells using seven base editors (BE3; BE3_UdgX; BE3_UdgX*; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG) are shown in FIGS. 7 through 15 . These figures show the results for C to G editing at the most edited position (C6) at the three representative sites that have high, medium, and low tolerance to sequence perturbation from standard C to T editing.

Results of C to G base editing at HEK2, RNF2, and FANCF sites in UDG−/− cells using various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) are shown in FIGS. 16 through 24 .

Results of C to G base editing at HEK2, RNF2, and FANCF sites in REV1−/− cells using various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) are shown in FIGS. 25 through 30 .

Results of C to G base editing at HEK2, RNF2, and FANCF sites in the three respective cell types (WT, UDG−/−, and REV1−/− cells) using various C to G base editors (BE3; BE3_UdgX; BE2_UNG; BE3_UNG; BE2UdgX_On; BE3UdgX_On; and SMUG1) are summarized in FIGS. 31 and 32 .

Example 2: C to G Approach 2—Increase C Incorporation Opposite an Abasic Site

An increase in the preference for C integration opposite an abasic site should lead to an increase in total C to G base editing. A schematic for this approach and base editors used in this approach is illustrated in FIGS. 33 and 34 . Various polymerases that can be used in this approach for C to G base editing are shown in FIG. 35 . Briefly Abasic site generation leads to C to non-T product formation. Rev1 has dC transferase activity. Eliminating this pathway or altering how abasic lesions are repaired should lead to new base editors. Rev1−/− knockout cell lines should lack C to G editing if this pathway is solely responsible for formation of this product. The fusion of various polymerases should lead to repair of the opposite strand based on polymerase preference for repair opposite an abasic sites leading to increased C to G base editing. Exemplary base editors are illustrated in FIG. 36 .

Results of C to G base editing at HEK2, RNF2, and FANCF sites in WT cells using various base editors (BE3; BE3_UdgX; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG) are shown in FIGS. 37 through 39 .

Steady-state Kinetic parameters for one-base incorporation opposite an abasic site and G by human polymerases η, ι, κ, and REV1 are given in Table 2. See, Choi et al. J mol Bio. 2010).

TABLE 2 Steady-state Kinetic parameters for polymerases η, τ, κ, and REV1 k_(cat)/K_(m) dNTP K_(on) k_(cat) (mM⁻¹ selectivity Relative Polymerase Template dNTP (μM) (s⁻¹) s⁻¹) ratio^(a) efficiency^(b) η AP site A 40 ± 6  0.12 ± 0.004 3.0 0.95 0.065 T 290 ± 50 0.92 ± 0.05 3.2 1 0.070 G  8.5 ± 1.0  0.005 ± 0.0001 0.59 0.19 0.013 C 210 ± 20 0.14 ± 0.01 0.67 0.21 0.015 G C  2.6 ± 0.1  0.12 ± 0.005 46 1 τ AP site A 210 ± 40 0.54 ± 0.04 2.6 0.45 1.4 T 130 ± 20 0.74 ± 0.02 5.7 1 3.0 G 120 ± 10 0.47 ± 0.01 3.9 0.69 2.1 C  570 ± 140 0.77 ± 0.05 1.4 0.24 0.74 G C 300 ± 30 0.57 ± 0.02 1.9 1 κ AP site A 1600 ± 200 0.077 ± 0.005 0.048 0.77 0.00065 T 2300 ± 700 0.017 ± 0.002 0.0074 0.12 0.00010 G 400 ± 70 0.0032 ± 0.0002 0.008 0.13 0.00011 C  780 ± 220 0.049 ± 0.005 0.063 1 0.00085 G C  3.8 ± 0.5 0.28 ± 0.01 74 1 REV1 AP site A 140 ± 50 0.000025 ± 0.000002 0.00018 0.0031 0.00019 T 190 ± 30 0.000072 ± 0.000003 0.00038 0.0067 0.00040 G 190 ± 50 0.000031 ± 0.000003 0.00016 0.0029 0.00017 C 210 ± 30 0.012 ± 0.001 0.057 1 0.061 G C 12.8 ± 50   0.012 ± 0.0003 0.94 1 ^(a)dNTP selectivity ratio, calculated by dividing k_(cat)/K_(m) for each dNTP incorporation by the highest k_(cat)/K_(m) for dNTP incorporation opposite AP site. ^(b)Relative efficiency, calculated by dividing k_(cat)/K_(m) for each dNTP incorporation opposite AP site by k_(cat)/K_(m) for dCTP incorporation opposite G.

Steady-state kinetic parameters for one-base incorporation opposite an abasic site and G by human polymerases α and δ/PCNA are given in Table 3.

TABLE 3 Steady-state Kinetic parameters for polymerases α and δ/PCNA Steady-state kinetic parameters for one-base incorporation opposite an AP site and G by human pols α and δ/PCNA k_(cat)/K_(m) dNTP K_(m) k_(cat) (mM⁻¹ selectivity Relative Polymerase Template dNTP (μM) (s⁻¹) s⁻¹) ratio^(a) efficiency^(b) α AP site A 570 ± 100 0.0083 ± 0.0001 0.015 1 0.0010 T 250 ± 60  0.00046 ± 0.00003 0.0018 0.12 0.00012 G 550 ± 120 0.00024 ± 0.00002 0.0004 0.027 0.00003 C 980 ± 50   0.00047 ± 0.000001 0.0005 0.033 0.00003 G C 0.42 ± 0.09 0.0064 ± 0.0003 15 1 δ/PCNA AP site A 25 ± 6  0.0067 ± 0.0004 0.27 1 0.012 T 62 ± 16 0.0060 ± 0.0004 0.097 0.36 0.0044 G 110 ± 20  0.010 ± 0.001 0.091 0.34 0.0041 C 880 ± 160 0.0069 ± 0.0006 0.0078 0.029 0.0004 G C 0.27 ± 0.05 0.0059 ± 0.0002 22 1 ^(a)dNTP selectivity ratio, calculated by dividing k_(cat)/K_(m) for each dNTP incorporation by the highest k_(cat)/K_(m) for dNTP incorporation opposite AP site. ^(b)Relative efficiency, calculated by dividing k_(cat)/K_(m) for each dNTP incorporation opposite AP site by k_(cat)/K_(m) for dCP incorporation opposite G.

TABLE 4 Polymerases that can be used for base editing approach 2. Polymerase Size (Amino Acids) Family X Beta 335 Lambda 575 Mu 494 Family B Alpha 1462 Delta 1107 Epsilon 2286 Family Y Eta 713 Iota 740 Kappa 870 Rev1 1251 Zeta (Rev3/Rev7) 3130

Example 3: C to G Approach 3—Increase Both Abasic Site Formation and C Incorporation

A schematic of a base editor for increasing both abasic site formation and C incorporation for increased C to G base editing is illustrated in FIG. 40 . Addition of polymerase tethered constructs, particularly Pol Kappa, increases C to G base editing. Results of base editing at the HEK2, RNF2, and FANCF sites using either Pol Kappa for Pol Iota tethered constructs is shown in FIG. 41 . Results of base editing using additional polymerase tethered constructs in WT cells at cytosine residues in the HEK2, RNF2, and FANCF sites are shown in FIGS. 42 through 47 . UDG 147 is an enzyme that directly removes T and increases the C to G base editing (FIGS. 42 through 44 ), while UDG 204 is an enzyme that directly removes C and increases C to G base editing (FIGS. 45 through 47 ).

Example 4: C to G Approach 4—Eliminate Alternative Repair Pathways to Increase C to G Flux

One way to improve C to G editing is to eliminate or downmodulate alternative repair pathways. AS one example, eliminating the repair pathway protein MSH2^(−/−) may lead to an increase in C to G base editing is shown in FIG. 48 . The results of C to G base editing at HEK2, RNF2, and FANCF sites in MSH2^(−/−) cells using various base editors (BE3; BE3_UdgX; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG) are shown in FIGS. 49 through 51 .

Example 5: C to G Approach 5—Expression of Components in Trans

One approach for identifying base editor components that function together is to express those components together in a cell, in trans. Once base editor components (e.g., polymerases, uracil binding proteins, base excision enzymes, cytidine deaminases, and/or nucleic acid programmable DNA binding proteins) that induce C to G mutations are identified, they can be tethered to generate base editors. Expressed UDG and UdgX variants fused to APOBEC-Cas9 nickase and simultaneously overexpressed TLS polymerases in trans lead to C to G editing at the RNF2 site. A schematic illustrating the expression of components in trans is shown in FIG. 52 .

Results of base editing at HEK2, RNF2, and FANCF in HEK293 cells using five different base editors (BE3; BE3_UdgX; BE2_UdgX_On; BE3_UdgX_On; BE2_UDG; and BE3_UDG) expressed, in trans, with various polymerases (Pol Kappa, Pol Eta, Pol Iota, REV1, Pol Beta, and Pol Delta) are shown in FIGS. 53 through 55 .

REFERENCES

-   1. Chan, K., Resnick, M. A., Gordenin, D. A. The choice of     nucleotide inserted opposite abasic sites formed within chromosomal     DNA reveals the polymerase activities participating in translesion     DNA synthesis. DNA Repair 12, 878-889 (2013). -   2. Choi, J. Y., Lim, S., Kim, E. J., Jo, A., and Guengerich F. P.     Translesion synthesis across abasic lesions by human B-family and     Y-family DNA polymerases alpha, delta, eta, iota, kappa, and Rev1.     Journal of Molecular Biology 404, 34-44 (2010). -   3. Dianov, G. L. and Hubsher U. Mammalian base excision repair: the     forgotten archangel. Nucleic Acids Research, 1-8 (2013). -   4. Fortini, P., Pasucci, B., Sobol, R. W., Wilson, S. H., and     Dogliotti, E. Different DNA polymerases are involved in the Short-     and lon-patch base excision repair in mammalian cells. Biochemistry     37, 3575-3580 (1998). -   5. Jiricny, J. The multifaceted mismatch-repair system. Nature Rev.     Molecular Cell Biology 7, 335-346 (2006). -   6. Katafuchi A. and Nohmi T. DNA polymerases involved in the     incorporation of oxidized nucelotides into DNA: their efficiency and     template base preference. Mutation Research 703, 24-31 (2010). -   7. Kavli, B., Slupphaug, G., Mol, C. D., Arvai, A. S., Peterson, S.     B., Tainer, J. A., and Krokan, E. H. Excision of cytosine and     thymine from DNA by mutants of human uracil-DNA glycosylase. EMBO     15, 3442-3447 (1996). -   8. Krokan, H. E. and Bjoras, M. Base Excision Repair, Cold Spring     Harbor Perspectives in Biology, 1-22 (2013). -   9. Kunkel, T. A. and Erie, D. A. Eukaryotic mismatch repair in     relation to RNA replication. Annual Reviews Genetics 49, 291-313     (2015). -   10. Li, G. M. Mechanisms and functions of DNA mismatch repair. Cell     Research 18, 85-98 (2008). -   11. Lin, W., Xin, H., Wu, X., Yuan, F., and Wang, Z. The human REV1     gene codes for a DNA template-dependent dCMP transferase. Nucleic     Acids Research 27, 4468-4475 (1999). -   12. Mol, C. D., Arvai, A. S., Slupphaug, G., Kavil, B., Alseth, I.,     Krokan, H. E., and Tainer, J. A. Crystal structure and mutational     analysis of human uracil-DNA glycosylase: structural basis for     specificity and catalysis. Cell 80, 869-878 (1995). -   13. Prasad, R., Poltoratsky, V., Hou, E. W., and Wilson, S. H. Rev1     is a base excision repair enzyme with 5′ deoxyribose phosphate lyase     activity. Nucleic Acid Research, 1-10 (2016). -   14. Robertson, A. B., Klungland, A., Rognes, T., and Leiros, I. Base     excision repair: the long and the short of it. Cell Molecular Life     Sciences 66, 981-993 (2009). -   15. Sale, J. E., Lehmann, A. R., and Woodgate, R. Y-Family DNA     polymerases and their role in tolerance of cellular DNA damage.     Nature Rev. Molecular Cell Biology 13, 141-152 (2012). -   16. Sang, P. B., Srinath, T., Patil, A. G., Woo, E. J., and     Varshney, U. A unique uracil-DNA binding protein of the uracil DNA     glycosylase superfamily. Nucleic Acids Research, 1-12 (2015). -   17. Savva, R., McAuley-Hecht, K., Brown, T., and Pearl, L. The     structural basis of specific base-excision repair by uracil-DNA     glycosylase. Nature 373, 487-493 (1995). -   18. Slupphaug, G., Mol, C. D., Kavli, B., Arvai, A. S., Krokan, H.     E., and Tainer, J. A. A nucleotide-flipping mechanism from the     structure of human uracil-DNA glycosylase bound to DNA. Nature 384,     87-92 (1996). -   19. Weill, J. C. and Reynaud C. A. DNA polymerases in adaptive     immunity. Nature Rev. Immunology 8, 302-312 (2008). -   20. Yasui, A. Alternative excision repair pathways. Cold Spring     Harbor Perspectives in Biology, 1-8 (2013).

Example 6:—Cas9 Variant Sequences

The disclosure provides Cas9 variants, for example Cas9 proteins from one or more organisms, which may comprise one or more mutations (e.g., to generate dCas9 or Cas9 nickase). In some embodiments, one or more of the amino acid residues, identified below by an asterek, of a Cas9 protein may be mutated. In some embodiments, the D10 and/or H840 residues of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any one of the amino acid sequences provided in SEQ ID NOs: 4-26, are mutated. In some embodiments, the D10 residue of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9 provided herein, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, is mutated to any amino acid residue, except for D. In some embodiments, the D10 residue of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9, such as any one of the amino acid sequences provided in SEQ ID NOs: 4-26, is mutated to an A. In some embodiments, the H840 residue of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding residue in any Cas9, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, is an H. In some embodiments, the H840 residue of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, is mutated to any amino acid residue, except for H. In some embodiments, the H840 residue of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding mutation in any Cas9, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, is mutated to an A. In some embodiments, the D10 residue of the amino acid sequence provided in SEQ ID NO: 6, or a corresponding residue in any Cas9, such as any of the amino acid sequences provided in SEQ ID NOs: 4-26, is a D.

Cas9 sequences from various species were aligned to determine whether corresponding homologous amino acid residues of D10 and H840 of SEQ ID NO: 6 can be identified in other Cas9 proteins, allowing the generation of Cas9 variants with corresponding mutations of the homologous amino acid residues. The alignment was carried out using the NCBI Constraint-based Multiple Alignment Tool (COBALT(accessible at st-va.ncbi.nlm.nih.gov/tools/cobalt), with the following parameters. Alignment parameters: Gap penalties −11,−1; End−Gap penalties −5,−1. CDD Parameters: Use RPS BLAST on; Blast E-value 0.003; Find Conserved columns and Recompute on. Query Clustering Parameters: Use query clusters on; Word Size 4; Max cluster distance 0.8; Alphabet Regular.

An exemplary alignment of four Cas9 sequences is provided below. The Cas9 sequences in the alignment are: Sequence 1 (S1): SEQ ID NO: 23|WP_0109222511 gi 499224711|type II CRISPR RNA-guided endonuclease Cas9 [Streptococcus pyogenes]; Sequence 2 (S2): SEQ ID NO: 24|WP_039695303|gi 746743737|type II CRISPR RNA-guided endonuclease Cas9 [Streptococcus gallolyticus]; Sequence 3 (S3): SEQ ID NO: 25|WP_045635197|gi 782887988|type II CRISPR RNA-guided endonuclease Cas9 [Streptococcus mitis]; Sequence 4 (S4): SEQ ID NO: 26|5AXW_A|gi 924443546|Staphylococcus Aureus Cas9. The HNH domain (bold and underlined) and the RuvC domain (boxed) are identified for each of the four sequences. Amino acid residues 10 and 840 in S1 and the homologous amino acids in the aligned sequences are identified with an asterisk following the respective amino acid residue.

S1    1 --MDKK- YSIGLD*IGTNSVGWAVITDEYKVESKKEKVLGNTDRESIKENLI--GALLFDSG--ET AEATRLKRTARRRYT   73 S2    1 --MTKKN YSIGLD*IGTNSVGWAVITDDYKVPAKKMKVIGNTDKEYIKENLL--GALLFDSG--ET AKATRLKRTARRRYT   74 S3    1 --M-KKG YSIGLD*IGTNSVGFAVITDDYKVPSKKMKVLGNTDKRFIKKNLI--GALLFDEG--TT AEARRLKRTARRRYT   73 S4    1 GSHMKRN YILGLD*IGITSVGYGII--DYET-----------------RDVIDAGVRLFKEANVEN NEGRRSKRGARRLKR   61 S1   74 RRKNRICYLQEIFSNEMAKVDDSFFHRLEESFLVEEDKKHERHPIFGNIVDEVAYHEKYPTIYHLRKKLVDSTDKADLRL  153 S2   75 RRKNRLRYLQEIFANEIAKVDESFFQRLDESFLTDDDKTEDSHPIFGNKAEEDAYHQKFPTIYHLRKHLADSSEKADLRL  154 S3   74 RRKNRLRYLQEIFSEEMSKVDSSFFHRLDDSFLIPEDKRESKYPIFATLTEEKEYHKQFPTIYHLRKQLADSKEKTDLRL  153 S4   62 RRRHRIQRVKKLL--------------FDYNLLTD--------------------HSELSGINPYEARVKGLSQKLSEEE  107 S1  154 TYLALAHNIKFRGHFLIEGDLNPDNSDVDKLFIQLVQTYNQLFEENPINASGVDAKAILSARLSKSRRLENLIAQLPGEK  233 S2  155 VYLALAHMIKFRGHFLIEGELNAENTDVQKIFADFVGVYNRTFDDSHLSEITVDVASILTEKISKSRRLENLIKYYPTEK  234 S3  154 TYLALAHNIKYRGHFLYEEAFDIKNNDIQKIFNEFISIYDNTFEGSSLSGQNAQVEAIFTDKISKSAKRERVLKLEPDEK  233 S4  108 FSAALLHLAKRRG----------------------VHNVNEVEEDT----------------------------------  131 S1  234 KNGLFGNLIALSLGLTPNFKSNFDLAEDAKLQLSKDTYDDDLDNLLAQIGDQYADLFLAAKNLSDAILLSDILRVNTEIT  313 S2  235 KNTLFGNLIALALGLQPNEKTNFKLSEDAKLQFSKDTYEEDLEELLGKIGDDYADLFTSAKNLYDAILLSGILTVDDNST  314 S3  234 STGLFSEFLKLIVGNQADFKKHFDLEDKAPLQFSKDTYDEDLENLLGQIGDDFTDLFVSAKKLYDAILLSGILTVTDPST  313 S4  132 -----GNELS------------------TKEQISRN--------------------------------------------  144 S1  314 KAPLSASMIKRYDEHHQDLTLLKALVRQQLPEKYKEIFFDQSKNGYAGYIDGGASQEEFYKFIKPILEKM--DGTEELLV  391 S2  315 KAPLSASMIKRYVEHHEDLEKLKEFIKANKSELYHDIFKDKNKNGYAGYIENGVKQDEFYKYLKNILSKIKIDGSDYFLD  394 S3  314 KAPLSASMIERYENHQNDLAALKQFIKNNLPEKYDEVFSDQSKDGYAGYIDGKTTQETFYKYIKNLLSKF--EGTDYFLD  391 S4  145 ----SKALEEKYVAELQ-------------------------------------------------LERLKKDG------  165 S1  392 KLNREDLLRKQRTFDNGSIPHQIHLGELHAILRRQEDFYPFLKDNREKIEKILTFRIPYYVGPLARGNSRFAWMTRKSEE  471 S2  395 KIEREDFLRKQRTFDNGSIPHQIHLQEMHAILRRQGDYYPFLKEKQDRIEKILTFRIPYYVGPLVRKDSRFAWAEYRSDE  474 S3  392 KIEREDFLRKQRTFDNGSIPHQIHLQEMNAILRRQGEYYPFLKDRKEKIEKILTFRIPYYVGPLARGNRDFAWLTRNSDE  471 S4  166 --EVRGSINRFKTSD--------YVKEAKQLLKVQKAYHQLDQSFIDTYIDLLETRRTYYEGP--GEGSPFGW------K  227 S1  472 TITPWNFEEVVDKGASAQSFIERMTNFDKNLPNEKVLPKHSLLYEYFTVYNELTKVKYVTEGMRKPAFLSGEQKKAIVDL  551 S2  475 KITPWNFDKVIDKEKSAEKFITRMTLNDLYLPEEKVLPKHSHVYETYAVYNELTKIKYVNEQGKE-SFFDSNMKQEIFDH  553 S3  472 AIRPWNFEEIVDKASSAEDFINKMTNYDLYLPEEKVLPKHSLLYETFAVYNELTKVKFIAEGLRDYQFLDSGQKKQIVNQ  551 S4  228 DIKEW---------------YEMLMGHCTYFPEELRSVKYAYNADLYNALNDLNNLVITRDENEK---LEYYEKFQIIEN  289 S1  552 LEKTNRKVTVKQLKEDYFKKIECFDSVEISGVEDR---FNASLGTYHDLLKIIKDKDFLDNEENEDILEDIVLTLTLFED  628 S2  554 VFKENRKVTKEKLLNYLNKEFFEYRIKDLIGLDKENKSFNASLGTYHDLKKIL-DKAFLDDKVNEEVIEDIIKTLTLFED  632 S3  552 LEKENRKVTEKDIIHYLHN-VDGYDGIELKGIEKQ---FNASLSTYHDLLKIIKDKEENDDAKNEAILENIVHTLTIFED  627 S4  290 VFKQKKKPTLKQIAKEILVNEEDIKGYRVTSTGKPEF---TNLKVYHDIKDITARKEII---ENAELLDQIAKILTIYQS  363 S1  629 REMIEERLKTYAHLFDDKVMKQLKR-RRYTGWGRLSRKLINGIRDKQSGKTILDFLKSDGFANRNFMQLIHDDSLTFKED  707 S2  633 KDMIHERLQKYSDIFTANQLKKLER-RHYTGWGRLSYKLINGIRNKENNKTILDYLIDDGSANRNFMQLINDDTLPFKQI  711 S3  628 REMIKQRLAQYDSLFDEKVIKALTR-RHYTGWGKLSAKLINGICDKQTGNTILDYLIDDGKINRNFMQLINDDGLSFKEI  706 S4  364 SEDIQEELTNLNSELTQEEIEQISNLKGYTGTHNLSLKAINLILDE------LWHTNDNQIAIFNRLKLVP---------  428 S1  708

 781 S2  712

 784 S3  707

 779 S4  429

 505 S1  782 KRIEEGIKELGSQIL-------KEHPVENTQLQNEKLYLYYLQNGRDMYVDQELDINRLSD----YDVDH*IVPQSFLKDD  850 S2  785 KKLQNSLKELGSNILNEEKPSYIEDKVENSHLQNDQLFLYYIQNGKDMYTGDELDIDHLSD----YDIDH*IIPQAFIKDD  860 S3  780 KRIEDSLKILASGL---DSNILKENPTDNNQLQNDRLFLYYLQNGKDMYTGEALDINQLSS----YDIDH*IIPQAFIKDD  852 S4  506 ERIEEIIRTTGK---------------ENAKYLIEKIKLHDMQEGKCLYSLEAIPLEDLLNNPFNYEVDH*IIPRSVSFDN  570 S1  851

 922 S2  861

 932 S3  853

 924 S4  571

 650 S1  923

1002 S2  933

1012 S3  925

1004 S4  651

 712 S1 1003

1077 S2 1013

1083 S3 1005

1081 S4  713

 764 S1 1078

1149 S2 1084

1158 S3 1082

1156 S4  765

 835 S1 1150 EKGKSKKLKSVKELLGITIMERSSFEKNPI-DFLEAKG-----YKEVKKDLIIKLPKYSLFELENGRKRMLASAGELQKG 1223 S2 1159 EKGKAKKLKTVKELVGISIMERSFFEENPV-EFLENKG-----YHNIREDKLIKLPKYSLFEFEGGRRRLLASASELQKG 1232 S3 1157 EKGKAKKLKTVKTLVGITIMEKAAFEENPI-TFLENKG-----YHNVRKENILCLPKYSLFELENGRRRLLASAKELQKG 1230 S4  836 DPQTYQKLK--------LIMEQYGDEKNPLYKYYEETGNYLTKYSKKDNGPVIKKIKYYGNKLNAHLDITDDYPNSRNKV  907 S1 1224 NELALPSKYVNFLYLASHYEKLKGSPEDNEQKQLFVEQHKHYLDEITEQISEFSKRVILADANLDKVLSAYNKH------ 1297 S2 1233 NEMVLPGYLVELLYHAHRADNF-----NSTEYLNYVSEHKKEFEKVLSCVEDFANLYVDVEKNLSKIRAVADSM------ 1301 S3 1231 NEIVLPVYLTTLLYHSKNVHKL-----DEPGHLEYIQKHRNEFKDLLNLVSEFSQKYVLADANLEKIKSLYADN------ 1299 S4  908 VKLSLKPYRFD-VYLDNGVYKFV-----TVKNLDVIK--KENYYEVNSKAYEEAKKLKKISNQAEFIASFYNNDLIKING  979 S1 1298 RDKPIREQAENITHLFTLTNLGAPAAFKYFDTTIDRKRYTSTKEVLDATLIHQSIT--------GLYETRI----DLSQL 1365 S2 1302 DNFSIEEISNSFINLLTLTALGAPADFNFLGEKIPRKRYTSTKECLNATLIHQSIT--------GLYETRI----DLSKL 1369 S3 1300 EQADIEILANSFINLLTFTALGAPAAFKFFGKDIDRKRYTTVSEILNATLIHQSIT--------GLYETWI----DLSKL 1367 S4  980 ELYRVIGVNNDLLNRIEVNMIDITYR-EYLENMNDKRPPRIIKTIASKT---QSIKKYSTDILGNLYEVKSKKHPQIIKK 1055 S1 1366 GGD 1368 (SEQ ID NO: 23) S2 1370 GEE 1372 (SEQ ID NO: 24) S3 1368 GED 1370 (SEQ ID NO: 25) S4 1056 G-- 1056 (SEQ ID NO: 26)

The alignment demonstrates that amino acid sequences and amino acid residues that are homologous to a reference Cas9 amino acid sequence or amino acid residue can be identified across Cas9 sequence variants, including, but not limited to Cas9 sequences from different species, by identifying the amino acid sequence or residue that aligns with the reference sequence or the reference residue using alignment programs and algorithms known in the art. This disclosure provides Cas9 variants in which one or more of the amino acid residues identified by an asterisk in SEQ ID NOs: 23-26 (e.g., S1, S2, S3, and S4, respectively) are mutated as described herein. The residues D10 and H840 in Cas9 of SEQ ID NO: 6 that correspond to the residues identified in SEQ ID NOs: 23-26 by an asterisk are referred to herein as “homologous” or “corresponding” residues. Such homologous residues can be identified by sequence alignment, e.g., as described above, and by identifying the sequence or residue that aligns with the reference sequence or residue. Similarly, mutations in Cas9 sequences that correspond to mutations identified in SEQ ID NO: 6 herein, e.g., mutations of residues 10, and 840 in SEQ ID NO: 6, are referred to herein as “homologous” or “corresponding” mutations. For example, the mutations corresponding to the D10A mutation in SEQ ID NO: 6 or 51 (SEQ ID NO: 23) for the four aligned sequences above are D11A for S2, D10A for S3, and D13A for S4; the corresponding mutations for H840A in SEQ ID NO: 6 or 51 (SEQ ID NO: 23) are H850A for S2, H842A for S3, and H560A for S4.

Further, several Cas9 sequences from different species have been aligned using the same algorithm and alignment parameters outlined above. Several Cas9 sequences (SEQ ID NOs: 11-260 of the '632 publication) from different species were aligned using the same algorithm and alignment parameters outlined above, and is shown in .e.g., Patent Publication No. WO2017/070632 (“the '632 publication”), published Apr. 27, 2017, entitled “Nucleobase editors and uses thereof”; which is incorporated by reference herein. Amino acid residues homologous to residues of other Cas9 proteins may be identified using this method, which may be used to incorporate corresponding mutations into other Cas9 proteins. Amino acid residues homologous to residues 10, and 840 of SEQ ID NO: 6 were identified in the same manner as outlined above. The alignments are provided herein and are incorporated by reference. The HNH domain (bold and underlined) and the RuvC domain (boxed) are identified for each of the four sequences (SEQ ID NOs: 23-26). Single residues corresponding to amino acid residues 10, and 840 in SEQ ID NO: 6 are boxed in SEQ ID NO: 23 in the alignments, allowing for the identification of the corresponding amino acid residues in the aligned sequences.

EQUIVALENTS AND SCOPE, INCORPORATION BY REFERENCE

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. The scope of the present invention is not intended to be limited to the above description, but rather is as set forth in the appended claims.

In the claims articles such as “a,” “an,” and “the” may mean one or more than one unless indicated to the contrary or otherwise evident from the context. Claims or descriptions that include “or” between one or more members of a group are considered satisfied if one, more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process unless indicated to the contrary or otherwise evident from the context. The invention includes embodiments in which exactly one member of the group is present in, employed in, or otherwise relevant to a given product or process. The invention also includes embodiments in which more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process.

Furthermore, it is to be understood that the invention encompasses all variations, combinations, and permutations in which one or more limitations, elements, clauses, descriptive terms, etc., from one or more of the claims or from relevant portions of the description is introduced into another claim. For example, any claim that is dependent on another claim can be modified to include one or more limitations found in any other claim that is dependent on the same base claim. Furthermore, where the claims recite a composition, it is to be understood that methods of using the composition for any of the purposes disclosed herein are included, and methods of making the composition according to any of the methods of making disclosed herein or other methods known in the art are included, unless otherwise indicated or unless it would be evident to one of ordinary skill in the art that a contradiction or inconsistency would arise.

Where elements are presented as lists, e.g., in Markush group format, it is to be understood that each subgroup of the elements is also disclosed, and any element(s) can be removed from the group. It is also noted that the term “comprising” is intended to be open and permits the inclusion of additional elements or steps. It should be understood that, in general, where the invention, or aspects of the invention, is/are referred to as comprising particular elements, features, steps, etc., certain embodiments of the invention or aspects of the invention consist, or consist essentially of, such elements, features, steps, etc. For purposes of simplicity those embodiments have not been specifically set forth in haec verba herein. Thus for each embodiment of the invention that comprises one or more elements, features, steps, etc., the invention also provides embodiments that consist or consist essentially of those elements, features, steps, etc.

Where ranges are given, endpoints are included. Furthermore, it is to be understood that unless otherwise indicated or otherwise evident from the context and/or the understanding of one of ordinary skill in the art, values that are expressed as ranges can assume any specific value within the stated ranges in different embodiments of the invention, to the tenth of the unit of the lower limit of the range, unless the context clearly dictates otherwise. It is also to be understood that unless otherwise indicated or otherwise evident from the context and/or the understanding of one of ordinary skill in the art, values expressed as ranges can assume any subrange within the given range, wherein the endpoints of the subrange are expressed to the same degree of accuracy as the tenth of the unit of the lower limit of the range.

In addition, it is to be understood that any particular embodiment of the present invention may be explicitly excluded from any one or more of the claims. Where ranges are given, any value within the range may explicitly be excluded from any one or more of the claims. Any embodiment, element, feature, application, or aspect of the compositions and/or methods of the invention, can be excluded from any one or more claims. For purposes of brevity, all of the embodiments in which one or more elements, features, purposes, or aspects is excluded are not set forth explicitly herein.

All publications, patents and sequence database entries mentioned herein, including those items listed above, are hereby incorporated by reference in their entirety as if each individual publication or patent was specifically and individually indicated to be incorporated by reference. In case of conflict, the present application, including any definitions herein, will control. 

What is claimed is:
 1. A fusion protein comprising (i) a nucleic acid programmable DNA binding protein (napDNAbp) domain, wherein the napDNAbp domain when in association with a guide RNA (gRNA) specifically binds a target nucleic acid molecule; (ii) a cytidine deaminase domain, wherein the cytidine deaminase domain deaminates a cytosine base in the target nucleic acid molecule; and (iii) a uracil binding protein (UBP), wherein the UBP is a uracil DNA glycosylase (UDG) or a uracil base excision enzyme.
 2. The fusion protein of claim 1, wherein the uracil binding protein is a uracil base excision enzyme.
 3. The fusion protein of claim 1, wherein the uracil binding protein is a uracil DNA glycosylase (UDG).
 4. The fusion protein of claim 1, wherein the uracil binding protein comprises an amino acid sequence that is at least 85% identical to the amino acid sequence of SEQ ID NO: 48 (UDG), SEQ ID NO: 49 (UdgX), SEQ ID NO: 50 (UdgX*), SEQ ID NO: 51 (UdgX_On), or SEQ ID NO: 53 (SMUG1).
 5. The fusion protein of claim 4, wherein the uracil binding protein comprises the amino acid sequence of SEQ ID NO: 49 (UdgX), SEQ ID NO: 48 (UDG), SEQ ID NO: 50 (UdgX*), SEQ ID NO: 51 (UdgX_On), or SEQ ID NO: 53 (SMUG1).
 6. The fusion protein of claim 1, wherein the fusion protein comprises the structure: NH₂-[cytidine deaminase domain]-[napDNAbp domain]-[UBP]-COOH, wherein each instance of “]-[” comprises an optional linker.
 7. The fusion protein of claim 1, wherein at least one of (i) the cytidine deaminase domain and the napDNAbp domain, and (ii) the napDNAbp domain and the UBP are fused via a linker.
 8. The fusion protein of claim 1, wherein the fusion protein further comprises (iv) a nucleic acid polymerase domain (NAP).
 9. The fusion protein of claim 8, wherein the nucleic acid polymerase domain has translesion polymerase activity.
 10. The fusion protein of claim 8, wherein the nucleic acid polymerase domain is from Rev7, Rev1 complex, polymerase iota, polymerase kappa, or polymerase eta.
 11. The fusion protein of claim 8, wherein the nucleic acid polymerase domain comprises an amino acid sequence that is at least 85% identical to the amino acid sequence of any one of SEQ ID NOs: 54-64.
 12. The fusion protein of claim 8, wherein the fusion protein comprises the structure: NH₂-[cytidine deaminase domain]-[napDNAbp domain]-[UBP]-[NAP]-COOH; NH₂-[cytidine deaminase domain]-[napDNAbp domain]-[NAP]-[UBP]-COOH; NH₂-[cytidine deaminase domain]-[NAP]-[napDNAbp domain]-[UBP]-COOH; or NH₂-[NAP]-[cytidine deaminase domain]-[napDNAbp domain]-[UBP]-COOH; wherein each instance of “]-[” comprises an optional linker.
 13. The fusion protein of claim 1, wherein the napDNAbp domain comprises an amino acid sequence that is at least 85% identical to any one of SEQ ID NOs: 4-26.
 14. The fusion protein of claim 13, wherein the napDNAbp domain comprises the amino acid sequence of any one of SEQ ID NOs: 4-26.
 15. The fusion protein of claim 1, wherein the napDNAbp domain is a Cas9 nickase (nCas9) or a nuclease inactive Cas9 (dCas9).
 16. The fusion protein of claim 1, wherein the cytidine deaminase domain is a deaminase from the apolipoprotein B mRNA-editing complex (APOBEC) family.
 17. The fusion protein of claim 16, wherein the deaminase is selected from the group consisting of APOBEC1 deaminase, APOBEC2 deaminase, APOBEC3A deaminase, APOBEC3B deaminase, APOBEC3C deaminase, APOBEC3D deaminase, APOBEC3F deaminase, APOBEC3G deaminase, and APOBEC3H deaminase.
 18. The fusion protein of claim 1, wherein the cytidine deaminase domain comprises (i) an amino acid sequence that is at least 85% identical to an amino acid sequence of any one of SEQ ID NOs: 67-101.
 19. The fusion protein of claim 1, wherein the cytidine deaminase domain is a rat APOBEC1 (rAPOBEC1) deaminase comprising one or more mutations selected from the group consisting of W90Y, R126E, and R132E of SEQ ID NO:
 93. 20. A fusion protein comprising: (i) a first domain comprising an amino acid sequence that is at least 85% identical to the amino acid sequence of any one of SEQ ID NOs: 4-40; (ii) a second domain comprising an amino acid sequence that is at least 85% identical to the amino acid sequence of any one of SEQ ID NOs: 67-101; and (iii) a third domain comprising an amino acid sequence that is at least 85% identical to the amino acid sequence of any one of SEQ ID NOs: 48-53.
 21. A complex comprising a nucleic acid molecule and the fusion protein of claim
 1. 22. A pharmaceutical composition comprising the fusion protein of claim 1 and a pharmaceutically acceptable excipient.
 23. A method comprising contacting a nucleic acid molecule with the fusion protein of claim
 1. 24. A method of editing a nucleobase pair of a double-stranded DNA sequence, the method comprising: contacting a target region of the double-stranded DNA sequence with a complex comprising the fusion protein of claim 1 and a guide nucleic acid, wherein the target region comprises a target nucleobase pair; and thereby: inducing strand separation of said target region; and excising a cytosine or a thymine in a single strand of the target region.
 25. A method of treating a subject having or suspected of having a disease or disorder comprising administering the fusion protein of claim 1 ex vivo to a cell from the subject.
 26. The fusion protein of claim 20, wherein: (i) the first domain comprises the amino acid sequence of any one of SEQ ID NOs: 4-40; (ii) the second domain comprises the amino acid sequence of any one of SEQ ID NOs: 67-101; and (iii) the third domain comprises the amino acid sequence of any one of SEQ ID NOs: 48-53.
 27. The fusion protein of claim 1, wherein the uracil binding protein comprises the amino acid sequence of SEQ ID NO: 49 (UdgX).
 28. The fusion protein of claim 1, wherein the uracil binding protein comprises a UdgX or UdgX*.
 29. The fusion protein of claim 7, wherein the linker comprises the amino acid sequence of any one of SEQ ID NOs: 102-109, 120, and
 123. 30. The fusion protein of claim 18, wherein the fusion protein comprises an amino acid sequence of any one of SEQ ID NOs: 67-101.
 31. A cell comprising the fusion protein of claim
 1. 